1. Space and Place Are Cross-Cutting Concepts
As an introduction to this website, there are a few preliminary points I would like to touch upon. I’m an architect and the tradition wants architects to be sensitive to many different inputs from different disciplines. Precisely because my profession lies at the intersection of the Sciences and the Humanities, I’m used to looking at things and arguments from different perspectives: I believe a basic knowledge of different scientific and humanistic disciplines is an important asset for architects. Accordingly, with respect to the concepts of space and place, I cannot refrain from pointing out that dealing with such pervasive and universal concepts inevitably exposed my thinking to both scientific and humanistic considerations. Ultimately, I believe the concepts of space and place are cross-cutting concepts whose meaning to be elucidated inevitably calls for many different voices, from different branches of knowledge, to be taken into account.
2. Uncertainty of Interpretation
As Albert Einstein said in his introduction to Max Jammer’s acclaimed book ‘Concepts of Space’, there exists a far-reaching uncertainty of interpretation concerning the concepts of space and place. Einstein himself went through different periods in which he interpreted those concepts differently. Neither physicists nor philosophers agree with conclusions and many different interpretations throw us into a bit of confusion. And to make matters worse, in the wake of philosophy and physics every discipline has its idea and interpretation of those concepts: among others, mathematicians, historians, geographers, sociologists, psychologists, artists, architects, etc.; not to mentions politicians. They all have theories of space and place enlarging the horizons of many possible interpretations. All one can do is to be part of that debate, by trying, if possible, to find a convergence between different interpretations, renovating, or promoting, a proficient dialogue between all of the actors involved in the elucidation of those concepts, so that it becomes possible to orient oneself in a sea of different interpretations.
My specific position aims at enlarging the traditional boundaries of the discussion, initially aired by philosophers and physicists, by gathering and bringing into play the voice of those social and cultural actors who are directly, or even indirectly, engaged with questions of space and place. In the overall, I believe that a convergence toward a shared understanding of those concepts will result as soon as cultural and social forces are ready to embrace a new, shared vision of the world similarly to what happened in the past: I’m thinking about the prevailing convergence of interests between different social and cultural actors in the period soon after Newton’s redefinition of the concepts of space, place and time. From here derives my conviction that no single idea, theory or event can be the catalyst for universal processes if the overall conditions are not favourable. The redefinition of concepts of place and space is a historical process. Ultimately, there is a great deal at stake behind the redefinition of the concepts of space and place.
3. Rethinking Space and Place: A Collective, Historical Undertaking
The ambitious program of redefining our ideas of space and place is an ongoing historical process that can only be successful if we are able to encompass different perspectives into a coherent and unitary framework and offer new theoretical and practical possibilities to the analysis of phenomena. Therefore, the program that I’m going to present here – the redefinition of the concepts of space and place – is ultimately a multifaceted collective undertaking, a line of research that has its roots in the past centuries. Allegorically, we could understand this line of research, which, I believe, will lead to a new enlarged meaning for those concepts, as a real socio-cultural journey: a new peripeteia  – this is how the American philosopher Edward S. Casey, called that journey; or, a caravan already on the move  toward a third watershed (after the preceding two, Aristotle and Newton), is the image used by the British theoretical physicists Julian B. Barbour to describe that journey from a scientific perspective. Since we’ve been entering an epoch in which information and knowledge can instantaneously and easily circulate among scholars and the intelligent reading public from different ages and different socio-cultural backgrounds, from all over the world, we have now the possibility to extend discussions on space and place beyond the traditional boundaries offering different perspectives to the phenomena involved in the redefinition of those two concepts.
One of the central concerns of this website is the periodical revisions of important concepts, such as concepts of space and place. These revisions happen in coincidence with critical historical moments of social and cultural change, following new scientific and philosophical modes of thinking through which we try to give different interpretations of the phenomena of reality. I think we are living one of those crucial historical epochs in the history of mankind. This question – the redefinition of the concepts of space and place – is especially relevant for architects, whose profession is traditionally rooted in the comprehension of those concepts.
4. The Arena of Things and the Arena of Thoughts
As regards my interpretation of the two concepts, I will take a distance from the traditional notions of space and place, that is: I will take a distance from space understood as a frame of reference that contains objects and places (the so-called ‘intangible medium’ as the counterpart of material entities); and I will take a distance as well from the notion of place as part of space, simple location, geographical or socially-constructed notion. I will argue that space is a derivative notion with respect to place: from an ontological perspective, I consider place the fundamental entity in which objects exist and out of which they emerge. Conversely, from a correlated epistemological perspective, I believe space is an ingenious concept, the result of historically traceable intellectual contributions to the quest for knowledge of physical reality; therefore, space has its domain of application in the interpretation of reality rather than in reality itself. To put it briefly, I believe place to be the arena of things, or – otherwise stated – the scene of all events; while I consider space as a useful idea of geometrical origin; therefore, it pertains to the arena of thoughts only. Taken together, space and place can help us to have a complete understanding of reality and its happenings, from different, yet complementary, perspectives: one more concrete the other abstract.
With respect to the concept of place, when I say ‘the arena of things’, I mean that things themselves are the arena: this fact paves the way for a background-independent model that shifts the focus of the debate from space – which I consider an abstract concept – to place, understood as an all-embracing concept where the concrete and the abstract are correlated; one – the abstract – emerging out of, and bringing forth, the other . This also calls for the elucidation of the relationship between object and subject, or, to put it differently, between concreteness and abstraction to which questions of space and place are closely interlaced. First and foremost, I understand reality as place, not space; reality is place-based long before being spatial or spatially-based.
5. Reality: A Choral Realm
Instead of relying on an apparent dualism between reality and thinking, we have to expose and elucidate their complementarity or correlation, if we want to attribute place and space a proper meaning and a new sense that can help us redefine our being in the world. If a virtuous circularity exists between the reality of facts and the abstract modes of knowledge through which we understand those facts, then, reality itself emerges like a powerful encompassing realm – a choral realm -, where concrete and abstract modes stand in reciprocal relation, offering new possibilities to the analysis of phenomena. If we do not attribute place and space a proper interpretation, and if we do not understand the reciprocity between the two, we may fall victim to fallacious reasoning. This fact could be a menace to our own existence. I think many of the problems (social, political, economic, environmental, etc.) we are facing at the dawn of this new millennium, are due to a short-circuit between the concrete limits of our physical existence – a realm of place – and the unlimited potential domain of creative thought – an abstract domain, a domain of space, indeed – where we make plans, theories, hypothesis and projects of any kind, without taking into account those ontologically founding boundaries properly. To sum up, and to begin with, I believe it is advisable to understand space as an abstract entity, and place as the concrete entity out of which the abstract emerges.
In order to remove some epistemological ambiguities that may arise, we obviously have to say that both terms – space and place – belong to the abstract linguistic domain we are confined into; nonetheless, while I believe the term ‘space’ is a linguistic abstraction from an abstract domain (I will argue that our modern conceptions of space stem from the domain of geometry – an abstract domain), the term ‘place’, to begin with, directly reports to the concrete realm of physical objects. This means that the black keyboard through which I’m writing these notes is something that exists as a concrete place – the place where I digit letters and numbers – with respect to other concrete places: my desk, my office, Milano, Italy, the Milky Way, etc. So, when we speak in terms of place, or places, we generally refer to the concrete world of keyboards, desks, pens, rocks, planets, trees, animals, etc., to their situation and happenings. At the same time, this keyboard, among the other qualities, has a certain shape: it is rectangular, or, better, the keyboard is a solid body with a rectangular basis. Actually, such concrete bodily extension is just an approximation of a geometrical form that I know as a rectangle – if I consider its surface -, or a parallelepiped – if I consider the whole of its body. Such geometrical determinations help our understanding of the material object – a thing properly – and extend the possibilities to speak about it. These abstract determinations accompany the knowledge we have of that object, extending our possibilities of knowledge. Such abstract geometrical determinations (after which the modern concept of space was devised) are complementary aspects with respect to the concrete black plastic body of the keyboard understood as object-place among other objects-place. By the term space I refer to any abstract, imaginary, ideal or representational domain, which is complementary to the realm where concrete phenomena occur; so that I can also conceive of a beautiful black keyboard that can read my mind relieving me from the necessity to type any keys in order to let the text appear on the screen of my computer. Ultimately, such alternative, ideal, black futuristic keyboard exists in some space, or even within some imaginary, fantastic, place, just like those represented in books or films, for instance. I interpret spaces (and imaginary places) as standing on a different ontological ground with respect to the concrete reality of physicochemical, biological or social facts and events. From the mutuality between the two realms – the actuality of concrete facts and the intrinsically abstract knowledge we have of them – we can fully apprehend the world. While Plato defines such mediatory realm as ‘chōra’, ‘place’ is the way I understand it. Therefore, I will try to cope with reality – as a concrete fact – in term of place, or places, having both intensive and extensive magnitude; in term of space when I refer to reality as an ideal or possible domain that emerges from place. Then, for me, place and space define two different, yet complementary/correlated realms or domains. I will look into the nature of the two concepts, their history and their reciprocal relation.
6. Place and Space: Historical Meanings and Roles
Then, what are the meanings and the roles that space and place played in the human attempt to cope with reality? How did the multi-layered meaning of the two concepts come into being?
The concept of place has always been psychologically related to some sort of thing, matter or substance; place has always been considered the place of something, its physical situation – its placement properly – into this world, from which a primary relation between position – or location – and matter could be deduced. It was by means of abstract reasoning that the curious mind of the ancient Greeks bifurcated the thing from the place that intrinsically belonged to the thing itself (at ontological level, for me place and matter are one and the same, since I believe their distinction is mainly conceptual; hence their difference has to be elucidated at epistemological level). By separating matter from the place that is intrinsic to matter, we have broken that which could not be broken, thus reducing what originally was a unit into parts: matter on the one side, place on the other. The next step in this line of abstract reasoning was an abstraction of a higher order: since place could be conceived of in abstraction from matter, there was no reason for relating matter to a particular place: hereinafter, the substitution of the concept of place with the more neutral term ‘space’ as the support frame of reference for the existence and the motions of things and bodies.
7. A New World Vision
What I have described right above here, in a few words, is a historical process that took a couple of millennia to occur: the shift of meaning (and interest) from place to space was lengthy and difficult, and it occurred during the period from Aristotle to Newton. Ultimately, the concept of space prevailed over the concept of place and colonized the modern mind of people from scientists to philosophers, from architects to the man on the street. Nonetheless, now, more than three centuries after Newton, thanks to the joint contribute of philosophers like Kant, Whitehead and a list of phenomenological thinkers (Husserl, Heidegger, Merleau-Ponty above all) and thanks to the new scientific paradigm envisioned by special relativity, general relativity and quantum mechanics, our understanding of the world has changed and the meaning of the terms we’ve been using to express the fundamental characters of reality – space and place of course, but also matter, time, void, causality, etc. – is shifting again. While philosophers have been particularly active in rejecting the Newtonian notion of place as simple location in space and showed that behind place we always find a certain kind of materiality, or concreteness, from which abstract notions of space can be devised, from scientists we have learned that, beyond appearances, things or, better, matter is nothing other than a field of concentrated energy: where the concentration of energy is small, we call it field, where the concentration of energy is great, we call it matter – Einstein has taught us. The new understanding of the fundamental character of reality anticipated by Faraday, Maxwell and Einstein, is now expressed by physicists by means of the field-concept, and it states that reality, at a fundamental level, can be conceived of as a set of interacting fields – as the American Nobel laureate in Physics Steven Weinberg has said.
Even if the argument is still debated, I believe that such physical fields now include within themselves notions of spatiality and temporality, thereby relegating the old notion of space – spacetime, precisely – to the role of mere epiphenomenon (I should say ‘ideal phenomenon’, that is a useful idea ‘attached’ to the actual world: useful to describe the concrete phenomena of reality, which is ultimately a place). To sum up, I believe we need both perspectives – the scientific and the philosophical, or humanistic – to relinquish the old meanings of space and place, so that we can get to a new understanding of place as the ultimate entity (what is a physical field if not a physical state of place, precisely?). Since the times of Newton, many philosophers put into question the notion of absolute space and the notion of place, as mere locality dispersed into space, while we had to wait for Einstein and quantum physics before physicists put into question Newton’s concepts of space and place. As regards the concept of place from the scientific perspective, the traditional way we understand the relation between matter and location is especially investigated and put into question by quantum mechanics: for instance, quantum non-locality is a measured phenomenon that contradicts the classical relation between matter and locality; in certain circumstances two objects far apart from each other, by showing entangled properties, behave as if they’re a single physical system or entity. Moreover, in a quantized – or discrete – world, how can entities pass from place to place if there is not a continuous range of adjacent places? As far as I understand the new predictions of physics it seems to me that understanding place as ‘implacement’ , that is place as the concrete outcome of processes, or as a system of processes out of which entities emerge (get im-placed), and in which they exist, rather than a simple location for entities (hence a taking place rather than a position taken), may be compatible with the interpretation of a far wider spectrum of phenomena, included quantum phenomena of non-locality. By taking into account the perspective of quantum mechanics among other perspectives, the notion of place that I’m thinking of encompasses all of reality, understood as a quantum-mechanically entangled whole.
All things considered, after the relatively recent new modes of understanding physical reality, I believe those two orders of abstraction I’ve mentioned in the previous paragraph are going to be vindicated: i) matter and place cannot be separated from each other if we are ready to relinquish the old notion of place as simple location by extending its meaning to include different orders of processes as intrinsic characters necessary to the emergence, existence and correlation of phenomena understood as places themselves; ii) space turns out to be a fruitful abstract concept, an ingenious invention that the inquiring mind has used in the attempt to explain the ultimate nature of things and their behaviour.
In the overall, it seems to me that even in virtue of the quite recent scientific discoveries, the aforementioned paradigm of interrelatedness between fields acting at microscopic level can also be extended at higher levels, to envision the deep interrelation between processes – whence all phenomena emerge – as the image we could use in order to characterize the world-view of the present epoch as ‘systemic’. Then, inquiring into the nature of space and place is a physical, metaphysical and cosmological attempt, driven by philosophical (humanistic) and scientific considerations. If a new meaning for the concepts of space and place has to be considered, such reformulation of concepts should be in tune with the quite recently discovered systemic understanding of life and the cosmos. Such systemic view, which is based on philosophic and scientific premises that discard the old deterministic, reductionist, and mechanistic modes of thoughts and methods, favours a unified vision of the complex phenomena out of which and in which reality emerges as a unified whole. Concepts of space and place – I mean the redefinition of those concepts – should now comply with this new systemic and holistic sensibility.
8. Place, Space, Time, Matter and the Fabric of Reality
To put it with different terms, the convergence between physical, metaphysical, and cosmological issues concerning the meaning of the concepts of space and place, I’m saying that I understand reality as having a fundamental kind of physicality – or concreteness – that we could metaphorically describe as a constitutive fabric (an all-embracing ‘plenum’ out of which anything emerges and in which anything exists) that keeps all things together and ordered. How should we call that fabric or intimate texture of the world? What is its appropriate name? Is it space, is it place, is it chōra? Is that fabric a dimensional continuum? Is it an extensive continuum? Is it an intensive continuum? Is that fabric absolute? Is it relative? Is it finite or is it infinite? Is it really a continuum, or is it something discrete or granular, like some physicists say? Can all of the phenomena of reality be reduced to such ultimate constitutive fabric, or may that fabric also emerge, in different guises, as a fundamental constitutive entity at different levels of complexity? If so, how does that fabric influence the multifaceted processes through which reality presents at different levels of complexity?
By inquiring into the nature of space and place I believe we cannot avoid answering those philosophically and scientifically founding questions. To begin with – this is just my opinion – the names we have attributed to that basic fabric since the times of Newton (absolute space after Newton, relative spacetime after Einstein and Minkowski) put a veil on basic ontological and epistemological issues that concern reality and our knowledge of it; hence, I will reconsider the way we understand that basic fabric that keeps all things together and ordered. I will reconsider its meaning and the name we have attributed to it. This is exactly what happened in the domain of physics, during the past decades, with respect to the field concept (the story of the field concept goes back in time to Faraday and Maxwell), which is now used by physicists to picture that basic, constitutive fabric. From my point of view – the perspective of one who is interested in understanding reality as encompassing realm where processes occur at different, independent, yet correlated inorganic, biological, social and symbolic levels – place is the name I would suggest to understand that physically constitutive fabric and to understand reality as a whole. However, I do not mean the common notion of place – as simple location or mere geographical or, even, socially constructed notion – but a revised notion of place, which can generalize and to take into account the entire set of humanistic and scientific contributes we have accumulated in the past centuries. Therefore, we should understand place as ‘implacement’, that is, place as ‘taking place’, not just of physical processes, but of a concrescent number of processes – from inorganic to organic, from social to symbolic processes – out of which entities emerge and in which they exist. As for the perspective of the physicist, this would mean understanding ‘physical fields’ (or anyway, fundamental entities or particles) as physical states of place, in so far as other states concur to identify reality as encompassing place of processes unfolding at different scales or levels of complexity.
Image 2, above, describes reality (R) as place emerging from processes occurring at different, independent yet correlated levels. According to this view, the entities that define reality may be understood as different states of place related to the different emergent levels at which specific processes occur: then, matter – the realm of physical fields, chemical elements or physical objects – is the place of physicochemical, or inorganic processes. Life – the realm of living organisms – is the place of biological, or organic processes. A society – the realm where groups of individuals interact – is the place of social processes. Finally, symbols – the realm of abstract, conscious, and creative thought, where moral and aesthetic values are also included – are the place of a set of intellectual, or symbolic processes, that differentiates societies into high developed cultures (this realm is exclusive to the humankind). Higher levels include lower levels. In the cultural context of the quite recently developed systemic view of the world, the theoretical framework I’m presenting here envisions reality as overarching place comprised between concrete and abstract processes (as to the relation between the different levels out of which and in which the different phenomena of reality emerge, this is a specific subject of investigation by Systems Theory). With this notion of place – the notion of place I want to speak about in this website, see the article What Is Place? What Is Space? for a synthetic definition – we embrace the realm of the inanimate and the animate as well, that is, we embrace the concrete as well as the abstract sides of reality as correlated or complementary facts. Then, any of the multifarious aspects through which reality presents to our senses, or to the instruments as prolongation of our senses, is a place: a place of processes out of which phenomena emerge and in which they exist. Therefore, differently from any reductionist world-view, the constitutive fabric of reality is not the only place (the place of physical processes out of which and in which other phenomena emerge and exist); every one of the four strands of reality – Matter, Life, Society and Thought, or, to put it differently, the Physical, the Living, the Social and the Symbolic – which is substantiated by that fabric, is a place. A fundamental, irreducible place (we are delineating a multilevel ‘ontology of place’). Then, in order to know reality as the encompassing place comprised between the concrete and the abstract, we cannot reduce phenomena to a single fundamental form of knowledge, but we have to investigate the relations that exist between the different levels of reality explained by the different disciplines through which we try to understand the phenomena of reality (I mean physics, chemistry, biology, social sciences… and the many different strands into which abstract thought is divided, that is, philosophy, mathematics, arts, architecture…). This calls for active participation, collaboration and transdisciplinary dialogue between the many different actors involved in the quest for knowing reality as a complex system so that knowledge itself can ultimately acquire a unified structure. Outside such a unified, non-reductionist and non-deterministic vision of reality and knowledge, no explanatory or predictive theory can have the right to be called a ‘theory of everything’. Ultimately, reality is a place, or, otherwise said: any aspect of reality unfolding at different levels of complexity can be defined and understood as place.
9. New Concepts for a New Era
What could we learn from the quite recent lessons of the Sciences and the Humanities? Fundamentally, that we should interpret space and place differently from the common belief: place is not simply a position in space or a ‘simple location’ for matter – to quote a famous expression by the Anglo-American philosopher and mathematician Alfred N. Whitehead – , but it should be understood as the concretization of processes through which matter and time (as duration) present themselves. In other words, the meaning of place, its basic sense, is given by the unfolding events, or processes, that codetermine material extension, location, and duration of the entities (that is: the What, the Where and the When as seamless parts of any physical entity in relation to the What, the Where and the When of other entities) that emerge out of those processes. Actually, the co-presentation of physical extension, localization and duration of entities – this is the way I understand the process of ‘implacement’ of physical matter – determines the appearance of reality (or any phenomena of reality) as a place, or as a system of places. That’s what I mean when I say that physical reality is a place and ‘place’ is primarily a ‘taking place’ – in the sense of occurrence or happening -, that is a place of processes. However, by the term ‘implacement’ we should not intend the concretization of physical matter only, in a specific location and temporal extension, but, within a wider perspective, we should intend it as the actualization (presentation as occurrence or ‘taking place’) of a concrescent chain of processes – from inorganic to biological, from social to symbolic or intellectual processes – so that place becomes the fundamental unit – either understood as physical entity or as abstract concept – through which inquiring into the nature of reality at any level, from the micro to the macroscale. This meaning of place subsumes other meanings by generalization and includes them as special cases (the old character of location/localization attributed to place – that is the aboriginal Where, abstracted from the What and the When of an entity actualized by processes – still holds, even if it is now clear that such specific character – or property – cannot be thought of in abstraction from other characters, i.e. duration and extension).
As regards our particular position of living beings within a cosmos populated by other sentient organisms and physical bodies, the things that we see, touch, hear, smell or taste and with respect to which we act, are just the place of processes we are engaged in, together with other organisms, bodies and the physical environment all around us. All together, we re-constitute a primordial kind of unity (a unit of experience-and-place in the case of living beings). Again, place is nothing other than the term that we should use to indicate the appearance – a presence in any effect – of an intricate web of processes under the guise of matter: as human beings, we do not perceive processes unfolding at any scale, but we just perceive the result of those processes – under the form of physical presence or existence – starting from the biological boundaries in which and out of which we emerge. We are an active part of those processes. This is my interpretation of the term place as ‘implacement’, or as a system of processes spanning from sub-atomic to macro scales, and, more extendedly, from physicochemical to intellectual, or symbolic, levels, when we consider the active agency of the mind (both conscious and unconscious) in the process of knowledge.
Since place and space are (co-)related concepts, the aforementioned interpretation of the concept of place inevitably affects the way should interpret space, assigning it a different meaning with respect to the common belief: while place, to begin with, refers to that which is concrete and resides in the realm of actual phenomena – this is what the statement ‘the arena of things’ means -, space should be merely understood as an abstraction, therefore residing in the abstract or ideal domain where the human mind represents reality or even invents new domains of it – this is what ‘the arena of thoughts’ means. Therefore, according to this view, space cannot be simply understood as the extensive and physical continuum of reality, unless we misplace the abstract for the concrete, the ideal, or possible, for the actual. In brief, I believe space should be primarily understood as a remarkably useful concept, a fictitious concept, an ingenious figment of our imagination, rather than a physical or an a-priori concept related to the different modes of perceiving/understanding the continuum of reality through which or within which actual phenomena are brought together in an intelligible way. 
Within this abstract perspective, such impalpable, extensive continuum we usually refer to when we use the term ‘space’, defines an abstract, ideal, permeating continuum, and not the actual fabric or the texture of reality. But, I interpret such abstract, ideal and permeating character that space has, somewhat differently from Kant: if we necessarily have to attribute sensation and cognition a certain degree of ‘natural’ abstraction from the enormous amount of raw data pertaining to the physical environment – I’m referring to innate forms of abstraction determined by many thousands years of biological evolution -, we have to attribute another order of abstraction to our understanding of space, which is – for me – different from Kant’s ‘a priori’ intuition. That order of abstraction I’m referring to deals with the most terrific capability of the human mind: the capability to consciously invent new abstract domains to extend the edge of knowledge (in the case of space, this new domain is the domain of geometry within a modern perspective: at this regards, the role of analytic geometry – invented by Descartes – was especially important with respect to the possibility of using a system of axis and coordinates to identify the position elements in an abstract space, which was the prelude to the Newtonian concept of absolute space).
Like Kant, I believe space to be the result of cognitive factors rather than external factors per se; therefore, space is not something ‘out there’, but is something ‘mental’ ultimately. However, I do not attribute an innate character, or an ‘a priori’ status to space, quite the contrary; I believe the concept of space was concocted by our minds, in our minds, in the course of many centuries of abstract reasoning and logical argumentation about the nature of reality. So I believe that behind the concept of space as an ‘abstract entity’ – a product of cognition, ultimately – there is something different with respect to what Kant taught us. In spite of this, I suspect that once the conceptualization of space has been laboriously envisioned during such a long period, that conceptualization may have changed, or is probably still changing the deep structure of our minds, thereby changing our modes of thought, of intuition and of representing reality; and by admitting this possibility we reconnect to the Kantian argumentation on the subjective and mental nature of space from a different perspective.
Therefore, concerning these latter claims, we cannot overestimate the importance of geometrical space – the integrated system of three dimensions formalized after the decisive contribute of Descartes – and its influence on the modes of thinking of the modern man. For instance, space (or ‘spacetime’ after Einstein and Minkowski) is the abstract domain within which physicists and mathematicians operate with arithmetical, geometrical, algebraic, analytical, or other abstract formulas, to invent new theories, prove abstract theorems or to explain concrete physical processes (therefore, any thought experiment to which physicists often recur in order to understand real phenomena, are idealized experiments that occur in space with no guarantee that their idealized results can be applied to reality-as-place); or, again, space is the abstract domain within which the architect imagines or designs new spaces that, if actualized into matter, lose their abstract character to create, or better, to modify concrete places. Again, space is the abstract domain that the chemist, or the biologist, uses to state innovative hypothesis for new chemical substances, medicines or to imagine new theories that may explain concrete chemical or biological processes. Or, that is the domain in which anthropologists or geographers make use of maps to represent or speak about meaningful places of a secluded tribe. In all of these cases, it is possible to establish a virtuous circularity between abstraction (here it lays the domain of space) and the stubborn facts concerning reality (a realm of place) that we try to investigate if the two perspectives are understood as complementary. Different, independent, yet complementary concepts: that’s what the analysis of place and space may reveal.
10. Entangled in Space: Geometrical Space versus Figurative Space
I’m also going to discuss the fact that if we neglect or overlook the epistemological question, by understanding space as a real/actual three-dimensional continuum (space, the container where concrete phenomena occur), we are exposed to different kinds of fallacies. Apart from the interpretations of space as concrete physical entity – which I reject – I will insist on the difference between space understood as a merely figurative term, a metaphor (that is, space as a term belonging to an abstract linguistic domain which is the sign for the actual three-dimensional continuum of reality) and space understood as a geometrically-rooted object from which the idea of three or tetra-dimensional extension may be extrapolated and applied to reality, and from which a rhizomatic proliferation of more abstract spaces can also be derived.
I believe it was from the cognitive possibilities opened up by the kind of geometrical space formalized after the ingenious intuition of Descartes that more complex spaces (and geometries) could be concocted: from the most intuitive of all, absolute space – envisioned by Newton – to its alternative, relative space – envisioned by Leibniz, at first -, and to those highly abstract spaces now used by theoretical physicists to inquire into the behaviour of matter at very small scales – for instance, this is the case of the so-called ‘Hilbert spaces’ with respect to the mathematical formalism of quantum mechanics; or, again, those non-Euclidean spaces that architects have been able to create and visualize with the help of CAD systems in the last couple of decades. 
Both interpretations of space – the figurative, or metaphorical, and the geometrical – are abstract, fundamentally; yet I believe the geometrical interpretation is more prolific – and less misleading – than the other, and more appropriate to explain the virtuous circularity that exists between space and place, between the abstract and the concrete. Contrary to appearances and the common sense, I think the figurative, or metaphorical, interpretation of space as the three-dimensional extensive continuum of reality (is this type of space what is often called ‘intuitive space’?) is a by-product of the geometrical interpretation, since the idea of space as indefinite – or infinite – ‘volumetric’ extension emerges from geometry and not just, or not directly, from reality: we needed at first Aristotle, then Descartes, and, finally, Newton before our minds could conceive of reality as a spatial container understood as a coherent system of three-dimensions (or four-dimensions if we include time) independent of its material content. 
In relation to the concepts of place and space, abstraction from reality – commenced by Aristotle’s theory of place -, geometrization of reality – culminating in Descartes’s formalization of the coordinates system (a decisive step to envision space as three-dimensional concept of geometrical origin) – and spatialization of reality – formalized after Newton’s reification of an abstract concept of space into ‘absolute space’ – are the three crucial historical moments without which no idea, image or understanding of space as we commonly have today, could have ever been concocted.
I believe it is an anachronism to think that our current (modern) spatially biased mode of understanding reality can be compared to that of our ancient predecessors (in other words, I’m questioning the possibility to attribute an ‘intuitive space’ to ancient people, as many say: what they could intuit was ‘place’, which included the extended character of things): this is a typical fallacy committed by those who overlook the many critical historical passages that took mankind from understanding reality as ‘plenum’ – or as a bounded place (Aristotle, by means of his theory of place, was the first to formalize with an abstract rational approach this kind of pre-scientific understanding of the cosmos) – to its understanding as bifurcated realm where matter – the plenum – exists in (empty) space. I believe there can be no consistent idea of space – understood as the extensive multidimensional continuum of reality we think about today -, if, before that, we do not have a consistent idea of space as a three-dimensional geometrical entity. Therefore, the association or identification of space with the continuum of reality we are now used to (the so-called intangible substance or medium), is anything but immediate, or innate: it took approximately two millennia of abstract reasoning and discussions before our spatialized modes of thinking about reality could be perfected and a few centuries more, before this mode of thinking could penetrate within the mind of everybody, so that, now, that association is almost immediate and spontaneous. So immediate and spontaneous that we have almost lost any trace of that difficult and lengthy historical process of learning where psychological, sociocultural and symbolic aspects played important and correlative roles for our modes of thinking about reality to be effectively changed. So immediate and spontaneous the association between space and the actual continuum has become, that we now live entangled in space – that is, we live entangled in a metaphor -, without even considering the risks behind that.
… all of us, grave or light, get our thoughts entangled in metaphors, and act fatally on the strength of them.GEORGE ELIOT, Middlemarch
11. Space as a Geometrical Object
It is important the difference between the two abstract, anti-substantivalist interpretations of space we are speaking of, namely: ‘figurative space’ and ‘geometrical space’. Under closer scrutiny, we discover that one – figurative space – could not be conceived without the preliminary existence of the other, at least as it was delineated in its most basic character: Cartesian space. Both kinds of spaces – the ‘generically figurative’ and the ‘specifically geometrical’ – are obviously the fruit of the abstracting agency of the mind, and both kinds of space have extension and dimensionality as their founding character; yet in the first case the abstract extension – understood as unitary system of relationships between height, breadth and depth – is supposed to be directly derived from the domain of reality (so that I can say: ‘the dancer is moving through the space of the stage’); while in the second case that system of related extensions is primarily understood as an abstract system derived from geometry and then superimposed to physical reality. In the latter case it is as if I can understand space as volumetric (three-dimensional) object only after an abstract geometry that I have learned to master through theory and practice has been cognitively internalized;  only after this abstract process of knowledge by learning has been accomplished, we can superimpose that abstract conceptualization – the abstract spatial system of coordinates – to the domain of reality, the domain where the dancer really acts on the stage. Then, the plan of the stage becomes the base of an imaginary parallelepiped and we can understand the dancer as if he is moving across its volume as a coherent system of three related dimensions. Ultimately, the modern idea of space as three-dimensional container is derived from such abstract volume; a volume that we can extend indefinitely in all directions regardless of any actual dancer or stage. A volume which persists even after the actual stage and the actual dancer have gone, giving us the illusion that what was abstractly conceptualized in our minds, by our minds, is ‘really out there’. As a matter of fact, it is only after these abstract passages – built upon a preliminary geometrical idealization – have been internalized we can say: ‘the dancer is moving through the space of the stage’; we cannot say that as a direct extrapolation from the actual continuum of reality (the immersive environment made of the actual floor, walls, curtains, ceiling etc.), which can only be the result of internal and external successive centrations (between the mind-body system and the circumambient world), to which the conscious intellectual program of geometrization and spatialization of reality has been superimposed in subsequent phases.
It is properly the fact that such abstract volume or extension of geometrical origin can be applied or superimposed to almost any concrete domain that has determined the fortune of the concept of space and the possibility for it to be reified and, consequently, for us to keep on speaking about physical space almost three centuries after its mathematical formalization (Descartes) and subsequent reification (Newton). Space – the concept of space as three-dimensional immersive entity we all know, that is ‘background space’ – is not a datum ‘over there’ that we have discovered with some difficulties in the course of evolution, but is something (an abstract system of reference – that’s why I believe Descartes should be considered the pioneer of the modern concept of space as geometrical object, rather than Pascal, Leibniz or other mathematicians who have dealt with the question-space more directly than Descartes) we have laboriously constructed by means of abstract reasoning through centuries of discussions: it is the outcome of intertwining sociocultural and symbolic processes. If we believe the contrary is true, if we believe space is ‘over there’, we would misplace for concrete that which is abstract. Place, not space, is that which really keeps things together, the real ‘datum’ through which everything emerges and in which anything exists, and moves. I believe the risk of misplacing the abstract for the concrete is much higher if we become used to the idea of space as a metaphor, that is if we simply become used to space as a figurative term to indicate the actual extensive dimensional continuum of reality – either we understand it as three or tetra-dimensional domain. The difficulty to get rid of the incredibly prolific idea of space understood as a physical entity – ‘physical space‘ – which is still deep-rooted in our modern minds, is a proof of what I’m saying. Conversely, if we get used to the idea that the modern concept of space is a mathematically-based concept, an abstract domain out of which different kind of spatial domains may emerge, we do not incur the risk to forget the epistemological veil behind that abstract term – or that risk is lower, I believe.
In brief, once rejected the concreteness of space (
‘physical space‘), I think that by understanding space as an abstract concept of mathematical origin (from which the idea of three or tetra-dimensionality as coherent system of dimensions is derived) rather than merely a figurative term, we become more conscious about the fact that we are abstracting from reality, hence we become more sensitive to the epistemological veil – a connection, properly – that exists between us and physical reality; our head can freely roam into space making hypothesis, theories, plans, creative thoughts or fantasies of any kind, but we instinctively know and feel that our feet are firmly put into place; in this way we instantly know that if we want our thoughts to be explicative of actual processes or anyway be directed to the concrete reality of facts and phenomena, they need to meet the constraints of reality as the place of physical, chemical, biological, social and intellectual processes, since this is ultimately the actual finite realm we live in.
To sum up: our typically modern mode of thinking about reality as extensive or dimensional continuum – that is, thinking about the fabric of reality as three-dimensional space or tetra-dimensional spacetime -, is not derived from the direct, intuitive, extrapolation of a system of integrated spatiotemporal extensions from the real world (the continuum in which we are immersed), but from the preliminary existence of an abstract structure of mathematical origin (either Euclidean or non-Euclidean) that we have learned to master by applying it to reality, and by superimposing it to reality itself thanks to a long historical and intellectual process that culminated in the genial intuitions of Descartes, Newton and Einstein, respectively. At this regards, in order for the geometrical concept of space to be conceptualized (the three-dimensional extent we usually refer to), we can never stress enough the importance of the studies made by the ancient and medieval astronomers (by relying on the presentation of Julian Barbour’s book the ‘Discovery of Dynamics’, I will dedicate a massive article to this question – the extended use of trigonometric techniques and their influence on the conceptualization of the modern concept of space, see the article Space and Place: A Scientific History – Part I), other than the studies made by geometers, philosophers, mathematicians, artists and architects in the Renaissance period – and even before -, with respect to the invention of geometrical perspective as an autonomous tool to represent aspects of reality with the proper order of coexistence and proportions between objects. This is a clear historical precedent were the interconnection of different types of knowledge, of sociocultural and symbolic processes, played complementary roles in the elaboration of concepts and a new world-view, as we also learn from the pages of the legendary text on the role of perspective with respect to knowledge – Perspective as Symbolic Form – written by the art historian Erwin Panofsky.
In the end, the new (modern) mode of thinking about reality, based on its geometrization and subsequent spatialization, needed many centuries before being accomplished: and it could only be accomplished after geometrical space – as an integrated system of three dimensions – was conceived, formalized and reified. We have almost completely forgotten all those difficult historical passages behind that laborious process of learning that changed our minds and, now, it is simple for us to say that space is either a physical or a figurative concept to identify the arena of things, because our minds are forged by at least three centuries with that conviction.
Within the complementary structure of reality that we are envisioning (a structure where the actual and the ideal, the concrete and the abstract are complementary or correlated) the concepts of space and place maintain a distinct ontological character. Were it not like that, it would be like mixing the idea of lemon with an actual glass of freshwater to get some cool lemonade. To drink your lemonade you need a real lemon, putting your potential plan – the idea of drinking fresh lemonade – into actualization. The same holds for space and place: space is the abstract medium that we have learned to manage in order to make complex plans and abstract theories to explain, or change, reality; space and place cannot blend or mix at the physical levels of reality; they are complementary notions staying on two different levels: one actual the other potential and ideal. It is properly their complementarity that allows squaring the circle of reality as encompassing domain where place and space coexist as representative notions of the concrete – or actual – and the abstract – or ideally possible and potential; each one with its distinct role, yet one relying on the other to complete itself and to offer a unitary vision of reality as an all-embracing system or realm (a place).
12. Spatial Conceptions, Scientific Revolutions and Society
By changing the modes of thinking about reality – from more concrete to more abstract modes – mankind directed towards a new historical phase: the Scientific Era. I’m going to dedicate part of this website to those crucial historical moments and the intermediate passages that gave our modes of thinking about reality a bias in favour of abstract against concrete, or pragmatic, attitudes; in favour of space against place.
Now, some centuries after the achievements of the Scientific Revolution and the Industrial Revolution (a natural offspring of the former), another epochal change is underway: the Information Revolution. If the Industrial Revolution had as its scientific and philosophical underpinning the knowledge and mindset based on the philosophy and the discoveries of – among others – Galileo, Descartes and Newton, the Information Revolution is based on different premises; and such premises, in turn, are based on a different understanding of the classical notions of space and place. As a matter of fact, the focus on the field concept, which is an operative concept for electromagnetism, relativity, and quantum physics as well, is explicative of that change (from the new physics different technologies emerged and will emerge, which are distinctive and different with respect to those technologies that stemmed from of the mechanical view of the Industrial Revolution). In spite of this epochal change, which is underway, the mindset of many cultural and social actors that constitute and govern large sectors of our society is still anchored to old scientific reductionist, deterministic and mechanistic modes of thinking and concepts. To govern the different technologies that emerged and still emerge since the discovery of electromagnetic phenomena and the new physics (relativity and quantum mechanics), and to foresee the consequences that might derive from the short-sighted application of those technologies, we need a completely different approach to concepts of space and place. This means that processes and phenomena of reality are always one step ahead with respect to the interpretation we give them (by using outworn interpretations of concepts): this is a possible cause of distress – at any level, social, political, economic, environmental, cultural, etc. – for a global society standing in the middle of an epochal transition. We still think about conventional notions of space and simplistic notions of place, as working concepts to explain phenomena in a society that is actually forged by processes that can only be explained in terms of fields, or ‘extended places’ (that is systemically entangled places of the kind I’m going to propose here), and abstract (ideal) spaces. A revision of the concepts of space and place is needed to fill the gap between the current processes of reality and the knowledge and interpretation we give them; no branch of knowledge will be left untouched by such revision of concepts.
New concepts for a new era: this is the ultimate reason for rethinking the concepts of space and place. By rethinking those concepts, I wish we could linger on the possibility to make those concepts coordinate and complementary – or mutually inclusive – to define a unique, encompassing domain where abstract and concrete modes of thought coexist, coevolving towards a poised state. In the present times this is a cogent necessity since we are entering a new era in the history of mankind, just a few centuries after the epochal changes brought about by the Scientific Revolution; apart from the philosophical and scientific changes brought about by each different historical period, the quite recently acknowledged and unprecedented product of the entanglement between symbolic, social, biological and physicochemical processes may be soon formalized in the form of a new geological era: the Anthropocene. The new epoch seems to be the carrier of even more abstract psychological attitudes towards physical reality (abstract concepts of space seem to prevail over the more concrete notion of place); it seems this abstract attitude aims at transcending the limits of the world in which we live. For the very first time in history, astonishing technological progress is offering us the possibility to physically experience and visualize the correlation between the concrete and the abstract, simultaneously (a Platonic dream comes true): I believe the Internet, Virtual Reality, Augmented Reality, Mixed Reality and all of the off-springs from the Information Revolution, can be interpreted as exemplifications of that ‘bastard receptacle’ – the Platonic chōra – were the concrete and the abstract coexist. However, despite the promises of technology, we are very far from reaching that aforementioned poised state – the poised state between abstract and concrete modes of thoughts – without which no real progress is attainable. Actually, risks are bigger than benefits if we do not drive the undergoing processes of change, by projecting the unlimited potentialities of our abstract (spatial) strategies – which constantly try to push forward the edge of knowledge – within the physical, biological and ecological limits of reality, understood as concrete place, whose physical, chemical and biological limits we cannot transcend.
The redefinition of concepts is ultimately a way to reinstate current social and cultural changes under a different perspective. I believe the concepts of space and place may be considered like detectors or trackers of epochal changes: they make those changes evident. On the traditional meaning of the concepts of space and place that we inherited from Newton (without forgetting those who prepared the ground for him), we have built the foundations of the modern capitalistic societies; on a new meaning for those concepts, we should build the society of the present and the immediate future, if we want to overcome the limits that derived from the old world-view (limits which are the cause of distress concerning our present social, political, economic, ecological, cultural… condition). Now, two and a half millennia after Plato, new technologies are giving us the opportunity to physically experience reality as a realm, or domain, correlatively comprised between the concrete and the abstract – I say between place and space: place as a system of processes in which and out of which physical, chemical, biological, ecological, sociocultural and symbolic phenomena emerge as an entangled (and conflicting) whole; space as its abstract, complementary, counterpart that allows us to investigate the complex nature of those phenomena by abstracting, or isolating, certain properties from the vastness of actual data that compose reality as an all-embracing whole, or place. As I have already said in the opening part (by mentioning the expressions used by the American philosopher Edward Casey and the British theoretical physicist Julian Barbour), the caravan is already on the move (or a third peripeteia has already begun) and will lead us to another redefinition of the main concepts through which we interpret reality (place and space have a key role); a sort of third systematization for those concepts (after the preceding two made by Aristotle and Newton, respectively), which is nothing but a third systematization for knowledge.
13. Architecture and Society
What do these global changes mean for architects? A different understanding of the concepts of space and place (which reflects a different mode of understanding reality, from which, in turn, a different social and cultural organization for the life of people results) means a new kind of architecture – whose seeds are among us since at least a few decades. By understanding architecture as a complex system within wider systems, architects are redefining their understanding of the notion of place; this, in turn, will affect the way they understand space and the way they understand the relationship between space, place and architecture. Not only is architecture embedded within sociocultural and symbolic processes; since environmental issues came out of scientific circles in the middle of the ‘80s, ecological processes began to be taken into consideration by a conspicuous number of practitioners (architects, engineers, urban planners, etc.); this means becoming conscious of the overall link between biological and physicochemical processes that influence – and are influenced by – the organization of communal life, which is ultimately shaped by a complex interplay of constraints acting at physical, chemical, biological, sociocultural and symbolic levels. This fact inevitably calls for a reinterpretation of the boundaries and the meaning of architecture at the dawn of a new era. 
Before I can introduce specific architectural arguments with respect to the revised notions of space and place that I call for here (the return to architecture after philosophical and scientific detours is definitely the ultimate mission for a website conceived by an architect), it is necessary for me to deal with the concepts of space and place at more theoretical levels to understand reality as complex system of place-and-space or, to put it differently, as system where concrete things-as-place and abstract spaces are understood in a complementary manner.
14. Reality, Knowledge, and Representation
As another example of the epistemological fallacy behind the interpretation of space as a concrete entity, I hope it does not sound too misleading if I say that understanding space as a concrete entity – that is, space as the actual arena where phenomena occur – is like being subjected to the risk of developing a disease because of the prolonged environmental exposition to the smoking pipe of a painting on the wall of our office. What I want to say is that I believe it is convenient to think about the concrete reality – its continuum as well as any of its aspects – in term of place, or places, and to think about space as a fictitious concept that we use to represent, think, or have knowledge of such reality-as-place. One thing is the concrete reality of facts, events or happenings; another thing is its representation or the conscious thoughts and reflections we have about it. Of course, the concrete reality of facts, happenings and actual objects are related to the way we represent them, or, better, to the knowledge we have of them as subjects. Objects and subject are the two parts of the system-reality: we have to investigate the circular relation that exists between the two in order to understand both parts and the system.
From an architectural point of view, attributing space an ideal domain only can be perceived as an unpleasant consequence to accept for architects grown up with theories (focused on space) developed in the past centuries. It is limiting – if not epistemologically wrong – to understand architecture as an exclusive domain of space (this is the traditional way architects and critics understand architecture since at least one century – see note 7 in the article The 3rd Skin), because space is a ghost in the end, while architecture is not. We do not live in metaphors – we do not live in space – but we live in concrete places; reality is a place – this is a refrain for me – and metaphors are a part of it, but we cannot misplace a part for the whole. Then, architecture should be understood – and taught in academies – as discipline regarding space-and-place: ‘architecture creates spaces and modifies places for dwelling’, is my definition of architecture. Not space and place taken individually as it is usual, but space and place taken as complementary concepts (one concrete, to begin with, the other purely abstract) out of which there can be no integral comprehension of architecture (provided we all agree this discipline should be in synchrony with the current epoch, where reality is understood as all-embracing phenomenon acting at different and correlate levels of complexity, from concrete to abstract, or symbolic, levels; and provided that a new, extended meaning for place and space is considered).
Space is first and foremost an ideal domain, the arena of abstract and creative thoughts: it is the permeating (ideal) background that sustains creative ideas or conceptualizations; it allows such creative ideas, thoughts and memories to stay related – if it is the case -, to take new forms and to express their potentiality (with no guarantee with respect to their possible actualization). There is a difference between the potentiality behind ideas and their actualization, the same way there is a difference between space and place. We can overlook that obvious fact. Because of its widespread use as a figurative concept space is a terrific mesmerizing concept that makes us lose focus on the difference between the concrete and the abstract, between the actual and the potential or ideally possible. By understanding space as a physical reality (the domain of concreteness), we are inclined to commit what, for other but related reasons, the Anglo American philosopher Alfred N. Whitehead called ‘fallacy of misplaced concreteness’. 
Apart from architects, the shift of vision requested to relinquish once for all space interpreted as physical entity (that is, space as ‘the arena of things’), and place interpreted as simple location, or geographical and socially-constructed notion may generate the same rejection for other categories of scholars, who are used to think of space as concurrent concept with respect to place, that is: a generic container – space – of specific situations – place; this fact implies the two concepts being on the same (physical) ground, which is contrary to the proposed framework.
In the end, I believe the common, unquestioned, understanding of space as the entity where phenomena occur (either we understand that entity absolute or relative) and of place as material matrix of specific settings unrelated to the whole, can be deceitful in uncritically mixing representative aspects of reality – an exclusive domain of space – with reality itself understood as all-embracing system of processes out of which and in which everything exists. Through my activity as a practising architect, as well as through the pages of this website, I aim to challenge this conventional mode of thinking about space and place.
To surpass any dualism or epistemological trap lurking between representational aspects of reality and reality itself – and in the end between space and place as representative aspects of those two different, yet correlate domains – we need to take further steps forward.
I believe there is a mutual relation, or circularity, between reality and the knowledge we have of it. To put it in terms of place and space this means that there is circularity between the concrete realm of place where things, or matter, emerge from processes, and space as an abstract mental domain that we use to figure out those processes and the behaviour of the actual entities that emerge from those processes (phenomena). I believe that it is precisely because of their intrinsic circularity that space and place are such pervasive concepts for us to explain or communicate experiences of the phenomenal world; a circularity that we do not acknowledge very often, and that concepts of space and place are effectively able to express if we are able to set up distinctions and continuities between the two concepts. Given that abstraction is a typical mode of human expression, it is opportune to consider thoughts, as well as memories, hopes, dreams or fantasies, values, belief, etc. as data belonging to the domain of reality, because such abstract cognitive aspects determine our human agency with respect to the world, and because the mind-body system, from which abstraction ultimately derives, certainly belongs to such concrete world, as one of the most complex results of physicochemical and biological evolution and adaptation. Ultimately, we have to attribute both concreteness and abstraction primary importance even though this fact does not entail that we can overlook the different nature between a concrete and an abstract thing; it is from the encounter between the object and the subject – as agent of abstraction – that a complementary mode of existence between the concrete and the abstract emerge; it is from that encounter that objects-as-place (or things-as-place) emerge, and the abstract ideas of space may emerge too, as one the most advanced abstract fictitious tools to understand the actual reality of facts, happenings or events.
We must acknowledge both the different nature and the complementary relation that exists between the concrete and the abstract, and, ultimately, between objects and subjects-as-living beings that are capable of abstraction (ultimately, abstraction – from the Latin ab-trahere, to draw from – is what characterizes the essence and activity of any living being and especially of man; to abstract is to draw some useful information – by means of sensation and cognition – from the unlimited amount of data that actually compose the realm of reality). It is from their encounter that reality reveals itself as the overarching realm – a complex place – comprised between the potentiality of an indefinite number of processes and their actualization into things (or things-as-place). In this unified realm, objects encounter and modify subjects, as well as subjects encounter and modify objects; ultimately, it is a difficult task to establish a line of demarcation – if there is any – between the two: we, subjects, are already with them, objects. It is the complementary scope of epistemology and ontology to reason about those intersecting limits, or boundaries, from which objective and subjective modes of existence result.
Concreteness and abstraction, objectivity and subjectivity, are different yet correlated aspects of reality, which is, ultimately, a unified and encompassing realm that cannot be simply split or reduced to its constituent parts without losing meaning, since one part relies on the other; one completes the other, or, again, one brings forth the other. It is this kind of positive circularity, or complementarity, that we should refer to when we think about ontological and epistemological aspects of reality. These considerations constitute the base for a doctrine of mutual immanence between objects and subjects; a mutuality, or correlation, which can reconcile dualism.
By analogy, the same holds for the concepts of space and place: one, space, as the complementary part of the other, place; and both concepts necessary to have a full grasp of reality, which is ultimately a choral realm or domain. If reality is understood as choral realm or domain (‘chōra’ is the name given by Plato to the mediatory realm between sensible and ideal forms), then space and place – the abstract and the concrete, the potential, or ideal, and the actual – coexist, that is, they chorally exist completing each other. Yet, in virtue of their different nature and the different levels at which they operate, they cannot blend, if not at a figurative or symbolic level of description.
In the end, the correlate structure of space and place that I’m thinking of aims at setting out a picture of reality as encompassing realm, where those concepts are circularly related between themselves as well as circularly related to other concepts, including of course objects and subjects as complementary modes of existence out of which reality emerge as unified realm: a concrete place. 
15. Reality and Its Continuum: Chōra or Place?
It seems an apparent contradiction may emerge between: i) the fundamental continuum of reality understood as ‘chōra’, the Platonic ‘receptacle’ interpreted as mediatory entity between the actual world of the sensible forms and the ideal world behind those forms; ii) the continuum understood as place, or system of places -, as I’m going to argue through the pages of this website; after all, this is the way I understand all of the aspects of reality and as well as its continuum, whose intensive and extensive properties are for me one and the same (their distinction is fictitious: such a distinction is analogous to the apparent distinction that Einstein draws between mass and energy, or matter and field – see note 8).
Given the fact that, from a linguistic and a philological point of view, ‘chōra’ and ‘place’ are neither synonymous nor similar (I believe ‘chōra’ is neither similar nor a synonymous term for ‘space’), we have apparently two possibilities to understand reality (the fundamental continuum that keeps reality together and related): ‘chōra’, or ‘place’. One, or the other. Nonetheless, I believe there is no irreconcilability between the two visions – the vision closer to the Platonic tradition and the vision closer to the revised interpretation of the concepts of space and place that I wish to propose here.
The emergence of an abstract realm – or an ideal realm in the platonic sense – is obviously subsequent to the emergence of the concrete realm of stubborn facts dictated by physical, chemical and by certain basic biological forces only; therefore, if we exclude the intervention of the mind, with its self-reflexive and inquiring agency, we should conclude that ‘place’ is the encompassing concept that describes the domain of reality as a bounded realm – a place indeed – creating and modifying its own states of order. To put it briefly, before the human mind appeared on this planet, physical reality could only be thought of as a place or a set of places: this is the natural world. As soon as the agency of the human mind, with its complex abstract products (creative thoughts, theories, hypothesis, etc.) becomes part of reality, the possibility to understand it as chōra emerges (chōra is the mediatory domain where the actual and the ideal meet), thereby excluding the alternative vision of reality understood as place. Then, if we should look at reality from an evolutionary point of view, it seems the emergence of a highly developed nervous system and the inquiring mind could constitute the threshold between understanding reality as place or as chōra. Yet, no contradiction exists between the two perspectives, since both concepts, ‘chōra’ and place, may define reality as encompassing realm between the concrete and the abstract, between the actual and the potential or ideal, provided we think of place as concrescent system of processes out of which, and in which, any concrete and abstract phenomena emerge. Therefore, in place, space or any abstract entities exist as parts of it (the common view, according to which place is understood as being a part of space, is turned upside down). Structured like this, place becomes an encompassing concept that contains anything you might think of. As soon as abstract conceptualization emerges (highly abstract concepts like ‘space’ belongs to the category that I have called ‘symbolic processes’ or even ‘intellectual processes’) a stratification of new abstract meanings is added to reality understood as a concrete place: ultimately, any form of abstraction depends from the pre-existence of place. If we understand the concept of place the way I have described – as implacement of entities from concrete to abstract – it can now be reconnected to the Platonic concept of chōra since, according to this perspective, both concepts (‘chōra’ and the reformed concept of place understood as system of concrescent entities emerging from processes) cope with the real/actual and the ideal as complementary modes of existence: both modalities – chōra and place – encompass what is real (or concrete) and what is ideal (or abstract).
In the background of such understanding of place as a system of concrescent processes out of which concrete and abstract entities emerge, a multilevel ontology begins to appear. The correlation between such fundamental entities that constitute the different levels of reality (a subject of ontology), and the way we have knowledge of such entities (a subject of epistemology) is essential to disentangle the complex relation between processes and reality, between abstraction and concreteness and, ultimately, between object and subject (or, better, between object and superject). To put it differently, I believe the ontological structure of reality understood as place emerging from a concrescent chain of processes is actualized – implaced – not exclusively through the processes out of which entities emerge as auto-referential modes of existence (this would imply the existence of an objective world ‘out there’ as distinct from any subjective presence ‘here’), but is actualized in correlation with the epistemological interpretation of those processes out of which the entities present at different levels: this implies the correlation between object and subject (or superject). This aspect is probably the most complex connotation behind the concept of place (and of space as a derivative concept from place) that I am questioning; its philosophical underpinnings I also would like to explore in this virtual place or space.
16. Place and Space: What Next?
I’m staying a little longer on this topic – place and/or ‘chōra’ understood as fundamental aspects of reality comprised between the concrete and the abstract, the actual and the ideal, the present and the past or future – because in the coming epoch we will have to learn how to get used to reality as a hybrid domain where the actual and the potential, or ideally possible, the present and the past or future coexist in unprecedented ways through the virtual; as a matter of fact, different types of hybrid domains – including virtual worlds, mixed reality, augmented reality and the likes – are completely changing our daily life.
All of these new domains, or realms, are directly affected by the way we understand the concepts of space and place. As soon as we can, we have to cope with the need to set up clear ontological and epistemological boundaries that differentiate and show continuities between meanings and domains of application of the two concepts – space and place -, to avoid fallacious modes of thinking may undermine our life and our future. It is important that the boundaries we set up unveil the continuity and the correlation between those concepts, because it is only in virtue of such continuity – a virtuous circularity, complementarity or correlation -, that a sustainable choral domain suspended between the concrete and the abstract may be implemented avoiding unexpected conflicts, either we understand that domain as ‘place’ or ‘chōra’.
Abstraction – which characterizes and distinguishes the human being with respect to other living beings – is a natural, powerful and fruitful mode of functioning for an organism, provided we do not incur into the fallacy of misplacing what is abstract for the concrete – fallacy of misplaced concreteness – or, vice versa, what is concrete for abstract – fallacy of misplaced abstractness. The re-interpretation of the concepts of space and place that I propose is a mode to avoid such accidental errors – at least, this is my wish -, by setting up clear ontological and epistemological boundaries between the two concepts.
Space and place are complementary notions that define two different and correlated modes through which we may grasp reality; their different nature cannot be underestimated or misplaced. We are now so used to consider space the actual domain where phenomena occur (space the arena of things), that a physicist or an astronomer can explain the circular motion of planets due to a folding of the spacetime structure because of the heavy mass of a star, or an architect can proudly affirm that architecture is an art, or science, of space. Either by a direct or figurative way, we are used to conferring space a physicality that it does not possess, actually. I believe the latter point is a key point for any interpretation of space different from the accepted tradition.
A subtle fallacy is veiled behind the interpretation of space (or spacetime) as a concrete entity: by conferring space a substantial quality – a quality that is closer to the concept of place since the times Aristotle put the question on the table and before modernity changed the modes of understanding the term – we fail to appreciate the richness of values and the complexity of facts and events that actually happen in the real world, since we cannot ascribe to space – properly in virtue of its abstract or highly selective character – the complex processual quality that is intrinsic to (any) concrete place, or to places. Moreover, by conferring space concrete materiality, which it does not possess, we charge it with restraints that ultimately may halt the unlimited potentialities behind that powerful abstract concept, thereby halting the potentiality of abstraction of the human mind.
Space and place are complementary, or circular, concepts which, taken together, describe reality as a unified realm. One – place – is concrete, the other – space – is abstract; one is actual, the other ideal; one bounded and finite, the other unbounded and infinite; one limited, the other limitless; one – place – is bounded to time (as duration), the other – space – is time-independent (admittedly this sounds quite ironic, but irony dissolves as soon as we think of space as an abstract concept); one expressing the concrescent and cogredient processuality of nature; the other expressing the abstracting processuality of the mind, which certainly belongs to nature but which aims at transcending it (this is especially true in the case of human beings).
Ultimately, dealing with questions of space and place without falling into metaphysical and epistemological traps is a complicated balancing act. To speak about space and place is like being in balance between the two aforementioned hazards: the fallacy of misplaced concreteness and its converse: the fallacy of misplaced abstractness. In the first case, we would mistake space for a concrete entity instead of understanding it as an abstract (ideal) entity, as it should be; in the second case, by uncritically assuming the Archytian possibility that ‘everything is in place, but place is in nothing’ , or by blindly assuming subjectivist and nominalist positions denying the fundamental reality of the physical world, we risk mistaking place, or any concept that is correlated to concrete entities, for an entity that violates what I consider an essential principle of understanding: the correlation between object and subject through the agency of the body and the mind (language has a critical function). Rethinking the meaning of space and place is a necessary step to avoid those traps.
As I have said in the opening part, such redefinition of concepts is a lengthy, ongoing historical process. Since space and place are fundamental concepts for the common sense of the laymen, as well as for architects, physicists, philosophers, mathematicians, artists, neurobiologists, social scientists, or even politicians (just to name few professions for which the elucidation of those concepts is particularly important), I try to give my contribution – as an architect and independent researcher – to such ongoing historical process, by focusing on aspects that can be worthwhile of consideration by experts from other disciplines. Given their historical legacy and their important role for knowledge, I believe we cannot dispense with those two concepts – space and place -, in our search for understanding happenings and events of reality, understood as encompassing domain where the actual and the ideal meet. We must understand and appreciate their differences as well as their reciprocity to delineate the characters of a new ‘Weltanschauung’ before we return to an age of barbarism chasing shadows on the back of a cave.
 Edward S. Casey, The Fate of Place: A Philosophical History (Berkeley: University of California Press, 1997), p. 340. See also paragraph 12 in this article, and the article Place and Space: A Philosophical History for a review and a summary of Casey’s book.
 Julian B. Barbour, The Discovery of Dynamics (New York: Oxford University Press Inc., 2001), 13. See also paragraph 12 in this article, and the article Space and Place: A Scientific History – Part I for a review and a summary of Barbour’s book.
 I believe that to overcome the dualism intrinsic to the traditional theories of space and place (a dualism between space, or place, and matter, which is the expression of an even more rooted dualism: the dualism between the concrete and the abstract) it is necessary to supersede old theories expressed in different epochs (I refer to Plato, Aristotle, Descartes, Leibniz, Newton, Mach, Einstein and more recent theories). Of course, this move requires [A] rethinking those concepts to avoid falling into anachronism; and [B] illustrating the relationship between the new extended meanings attributed to old concepts and the past theories.
 Chōra – whereby the English adjective ‘choral’ derives – is the name given by Plato to the realm where the always changing and perishable world of sensible forms meets the abstract domain where those forms ideally exist according to perfect and immutable mathematical relations. With respect to such Platonic perspective, I understand reality as the encompassing arena where things (what Plato called ‘sensible forms’) and thoughts (the abstract counterpart of sensible forms), exist in circular relation, one the complementary part of the other. The same circularity holds for the concepts of place and space, since one – place – refers to the arena of things (actually, I believe place is the very arena of things emerging from different kinds of process), the other – space – refers to the arena of thought (see the previous note). Through their circular relation we can define reality as one encompassing realm, where place and space coexist at different levels and with different roles and, most of all, in discontinuity with the prevailing view that wants space and place acting on the same (physical) level, although at different scales (place contained in space).
 In the end, it was through the work of mathematicians that the concept of space, conceived of as autonomous three-dimensional abstract entity – I mean the geometrical object – was formalized. Descartes’s analytical geometry played an important role at this regards. Before Descartes, Euclidean geometry was devoid of any reference to space as an autonomous three-dimensional concept – see also Einstein’s 1934 article: ‘The Problem Of Space, Ether, and The Field in Physics’. Maybe the idea of a coherent physical continuum was present in the mind of pre-scientific people at the level of intuition, yet this sort of intuition of the continuum, difficult to define, was not formalized into three-dimensional space until the modern epoch, thanks to the joint work of mathematicians, astronomers, philosophers, architects, artists, etc. – we are going to see this in detail.
 Within the framework that I’m going to delineate, the concepts of space and place may conflate at a symbolic level, so it is not always easy to set up clear boundaries between the two at such level. I’m thinking of thoughts, dreams, memories, fantasies or even hallucinations… Are dreams representations of places or are they spaces? In his ‘Poetics of Space’ is Bachelard speaking of spaces or places? Is Gotham City a place or is it an abstract space only? These and other related placial/spatial questions I also want to explore in this place.
 An invaluable source of historical and philosophical information concerning the alternate fortunes of the concepts of place (and space) is Edward Casey’s book ‘The Fate of Place – A Philosophical History’.
 This is the extended passage on the meaning of field and matter taken from the text ‘The Evolution of Physics’ by Einstein and Infeld: ‘Can we think of matter and field as two distinct and different realities? Given a small particle of matter, we could picture in a naive way that there is a definite surface of the particle where it ceases to exist and its gravitational field appears. In our picture, the region in which the laws of field are valid is abruptly separated from the region in which matter is present. But what are the physical criterions distinguishing matter and field? Before we learned about the relativity theory we could have tried to answer this question in the following way: matter has mass, whereas field has not. Field represents energy, matter represents mass. But we already know that such an answer is insufficient in view of the further knowledge gained. From the relativity theory we know that matter represents vast stores of energy and that energy represents matter. We cannot, in this way, distinguish qualitatively between matter and field, since the distinction between mass and energy is not a qualitative one. By far the greatest part of energy is concentrated in matter; but the field surrounding the particle also represents energy, though in an incomparably smaller quantity. We could therefore say: Matter is where the concentration of energy is great, field where the concentration of energy is small. But if this is the case, then the difference between matter and field is a quantitative rather than a qualitative one. There is no sense in regarding matter and field as two qualities quite different from each other…There would be no place, in our new physics, for both field and matter, field being the only reality.’ In Albert Einstein and Leopold Infeld, The Evolution of Physics (London: The Scientific Book Club, 1938), 256-258.
 Steven Weinberg, “The Search for Unity: Notes for a History of Quantum Field Theories”, Daedalus, Vol. 106, 1977, 23.
 I have taken the term implacement from Edward Casey. According to Casey, ‘the im- of implacement stresses the action of getting in or into, and it carries connotations of immanence that are appropriate to the inhabitation of places’. Edward S. Casey, Getting Back into Place: Toward a Renewed understanding of the World-Place (Bloomington: Indiana University Press, 1993), xiii, 315. I think this type of ‘active’ connotation is apt to describe what I mean for place when I say that a place is always a place of processes that cannot be severed from the entities – which are states of place – that accompany those processes; whenever processes become actual, they are actualized into entities-place or, simply, places. I believe the term implacement describes very well the intrinsic relation that I believe exist between processes and entities understood as places (or ‘elemental thing-place’ to take another fortunate expression from Casey, Ibid., page 216).
 For an overview of the new systemic understanding of life and the cosmos, I suggest Fritjof Capra’s widely accessible books; among others, his last published book (co-authored with the Italian Chemistry Professor Pier Luigi Luisi), The System View of Life (Cambridge: Cambridge University Press, 2014).
 Alfred N. Whitehead, Science and the Modern World (New York: Pelican Mentor Books, 1925).
 With the expression ‘unfolding events’ I mean the process through which an entity encounters another entity (so that any event is contained within – or emerges from – ‘the why’, ‘the how’, ‘the where’, ‘the what’ and ‘the when’ of reality); it is only from the encounters of two or more entities that reality may emerge – and can be understood – as a systemic whole.
 With respect to the process of knowledge, the active role of the mind (both unconscious and conscious) in its correlation with reality was beautifully expressed by two Chilean biologists, Humberto Maturana and Francisco Varela, through the expression ‘bringing forth of a world through the process of living’. Their theses represent a scientific way to escape the troublesome issue of irreconcilable dualism that affected Western Thought since its origins. The way I interpret reality through the concepts of place and space somehow reflects their way of relating knowledge to reality, the subject to the object, and, ultimately, the concrete to the abstract as a unique realm deriving from their reciprocity. The quotation in italics is taken from H.R. Maturana and F.J. Varela, The Tree of Knowledge (Boston: Shambhala, Revised edition, 1992), 11.
 As the American psychologist James J. Gibson once said about his pioneering studies in the field of visual perception, ‘The concept of space has nothing to do with perception (…). Geometrical space is a pure abstraction (…). The visual third dimension is a misapplication of Descartes’s notion of three axes for a coordinate system (…). Space is a myth, a ghost, a fiction for geometers’, in James J. Gibson, The Ecological Approach to Visual Perception (New York: Psychology Press Classic Editions, 2015), xv.
 According to Kant’s Inaugural Dissertation of 1770, ‘space is not something objective and real, neither substance, nor accident, nor relation; but subjective and ideal, arising by fixed law from the nature of the mind like an outline for the mutual co-ordination of all external sensations whatsoever’, in William Eckoff, Kant’s Inaugural Dissertation of 1770 (New York: Columbia College, 1894), 65.
 It seems to me that Kant, by introducing the concept of space within the realm of cognitive processes (in the Critique of Pure Reason), formalized another type of space, different from Descartes’s geometrical space and from Newton’s physical space: I’m referring to the type of mental space from which many theories of knowledge and perception were derived in one way or another (with regard to the notion of ‘perceptual space’, in many cases this is a misapplication of Kant’s theory since according to Kant space is a form of pure intuition, thereby its conceptualization is free of sensation, unrelated to the way our senses function; Kant’s argumentation with respect to the ideal nature of space is also quite different from Leibniz’s ideal space). Independently of Kant’s primacy in the history of modern thinking with respect to the cognitive nature of space (one could attribute that primacy to Leibniz as well, but this is not my point here), I believe that much confusion may arise by using the same concept – space – to explain different occurrences within different realms or domain – the geometrical, the physical and the cognitive or psychological -, if we underestimate the consequences of that transposition. With respect to the possibility of explaining physical phenomena by using the concept of space, that possibility has been long surpassed by the utilization of other concepts in physics (the spacetime concept and the field concept, respectively). Conversely, as far as I know, the traditional understanding of space as the arena of things is still widely used as mere representational concept in the field of psychology and in many theories of knowledge to which disciplines like, psychology itself, philosophy, geography, sociology, anthropology or architecture – just to name few – still refer to.
 More often than not – and more often than spaces based on simple Euclidean geometry – architectural spaces based on non-Euclidean geometries remain within their ideal domain in the form of drawings, renderings or models, to testify the great gap between idealization and actualization, between space and place. In this regard, the ultimate goal of an architect is the actualization of space into place – that’s what Architecture ultimately consist of -, while the actualization of space into paper or models is an intermediate passage – indeed necessary and vital for the discipline itself – for architects to thoroughly fill the gap between abstract space – the space of the project – and the real places where ideas contained in projects are reified, or actualized, during the phases of construction through the agency of physicochemical, biological, ecological, social (economic, political, technological etc.) and symbolic processes.
 Of course, this is an oversimplification that I will try to explain with more specific arguments in the historically-based articles that I will post in this website.
 With respect to the different phases – from topological to metrical – through which the concept of space is envisioned in the human mind, see also Jean Piaget and Barbel Inhelder, The Child’s Conception of Space (London, Routledge & K. Paul, 1956).
 In the essay ‘Perspective as Symbolic Form’, Panofsky was able to extend the relevance of a technical discourse on perspective to a global discourse on knowledge and the different world-view expressed by an epoch (Weltanschauung). By analysing the case of perspective, we can see how cognitive, psychological and technical practices of an epoch are interwoven, thus unveiling the reciprocal roles that biological, sociocultural and symbolic factors play in the process of knowledge. What is geometrical perspective if not another crucial historical moment to express one of the several abstract passages needed for the concept of space to be envisioned and developed by Western culture as means to understand, represent, mimic or surpass physical reality? I believe the invention of geometrical perspective pushed forward the edge of knowledge and extended our cognitive domain, preparing the mind to further explorations and expansions needed for the concept of geometrical space (as an integrated system of three dimensions) to be conceived – by Descartes – and reified – by Newton.
 The theory of relativity played an important part in stressing the importance of the field concept in physics as well; see Einstein and Infield, The Evolution of Physics, page 260. Einstein was the first who tried to devise a Unified Field Theory.
 The Nobel Prize-winning scientist Paul Crutzen, declared the Anthropocene to be the dawn of a new human-influenced epoch following the Holocene. Current environmental changes of the Earth-system are deemed to be the direct effect of the human agency on this planet. There is scientific evidence for this: rising CO2 levels, airborne particulates from fossil fuel burning in sediments, unprecedented levels of nitrogen and phosphorus in soils, pushed extinction rates of animals and plants, dispersed radioactive elements from nuclear bomb tests, etc. See Paul J. Crutzen, “The Anthropocene“, in Earth System Science in the Anthropocene edited by Ehlers and Krafft (New York: Springer, 2006).
 For the contingencies regarding the ‘third peripeteia’, see Edward Casey, The Fate of Place (Berkeley: University of California Press, 1997), 340; for those regarding ‘the caravan already on the move’, see Julian B. Barbour, The Discovery of Dynamics (New York: Oxford University Press Inc., 2001), 13.
 See note 23.
 The accidental error of mistaking the abstract for the concrete was called ‘Fallacy of Misplaced Concreteness’ by Alfred North Whitehead. In: Alfred N. Whitehead, Science and the Modern World (New York: Pelican Mentor Books, 1925), 52, 54, 59.
 Within the context of this kind of philosophical argumentation, the intricate relation between concepts of place, space, time, experience, subjectivity and objectivity, are arguments of thorough exploration by the Australian philosopher Jeff Malpas in the book ‘Place and Experience’.
 I borrow the term ‘superject’ from Whitehead’s ‘philosophy of organism’ according to which the subject emerges from the objective data of the world, therefore a ‘superject’ rather than a subject — see: Alfred North Whitehead, Process and Reality – An Essay in Cosmology (New York: The Free Press, Corrected edition, 1978), 88. From process philosophy I also take some argumentation in order to devise a possible solution to the dualism that afflicted Western thought; some of the complementary relations that Whitehead investigated – between process and reality, between object and subject – are part of my discourse on the differences and complementarities that exist between place and space as concrete – or objective – and abstract – or subjective/superjective – modes of experience. Always with respect to the original meaning of the term ‘subject’, it is extremely interesting Heidegger’s argumentation regarding the shift of meaning that the term underwent during the centuries, passing from being referred to the thing (‘sub-ject’ was the character that underlies a thing) to indicating the Cartesian ‘I’ of the proposition ‘I think’ as fundamental entity of reality – this is the way we currently understand the term ‘subject’ — see Martin Heidegger, What is a Thing? (South Bend: Gateway Editions, 1967), Section B, or the corresponding article in this website — therefore, during the centuries, the same term ‘subject’ reverted its meaning. While Heidegger tries to recover the old truth utilizing a hermeneutic approach, Whitehead by introducing a new term (superject) directly re-establishes the same old truth Heidegger refers to; two different approaches to the same fundamental fact. In the overall, it is not by chance that Heidegger’s reconstruction of the original truth about the subject and the object is parallel to the shift of meaning that the concept of place underwent from designating the concreteness of matter-as-implaced thing to a simple (abstract) location within space. The underlying process is the same and is referred to the passage from more concrete to more abstract modes of thinking about reality, a very long, multifaceted, process that regarded mankind in any of its aspects and culminated in the mechanical and deterministic worldview that emerged from Cartesian philosophy and Newtonian mechanics.
 See note 26.
 The literal quotation referred to Archytas of Tarentum is: ‘it is peculiar to place that while other things are in it, place is in nothing — see Edward S. Casey, Getting Back into Place, 14, 15; see also notes 48 and 53, p. 320. I will extendedly deal with Archytas’s and Aristotle’s theories of place in the forthcoming articles. As for the possibility of understanding place as simultaneously concrete and abstract you can also look at the article The Τόπος of a Thing.
Barbour, Julian B. The Discovery of Dynamics. New York: Oxford University Press Inc., 2001.
Capra, Fritjof and Luisi, Pier Luigi. The System View of Life. Cambridge: Cambridge University Press, 2014.
Casey, Edward S. Getting Back into Place: Toward a Renewed understanding of the World-Place. Bloomington: Indiana University Press, 1993.
—. The Fate of Place: A Philosophical History. Berkeley: University of California Press, 1997.
Crutzen, Paul J. “The Anthropocene“. In Earth System Science in the Anthropocene, edited by Ehlers and Krafft. New York: Springer, 2006.
Eckoff, William. Kant’s Inaugural Dissertation of 1770. New York: Columbia College, 1894.
Einstein, Albert. “The Problem of Space, Ether, and the Field in Physics”. In Ideas and Opinions. New York: Crown Publishers, Inc., 1954.
Einstein, Albert and Infeld, Leopold. The Evolution of Physics. London: The Scientific Book Club, 1938.
Gibson, James J. The Ecological Approach to Visual Perception. New York: Psychology Press Classic Editions, 2015.
Jammer, Max. Concepts of Space – The History of Theories of Space in Physics. New York: Dover Publications, Inc., 1993.
Heidegger, Martin. What is a Thing? South Bend: Gateway Editions, 1967.
Malpas, Jeff E. Place and Experience. Cambridge: Cambridge University Press, 1999.
Maturana, R. Humberto and Varela J. Francisco. The Tree of Knowledge. Boston: Shambhala, Revised edition, 1992.
Panofsky, Erwin. Perspective as Symbolic Form. New York: Zone Books, 1991.
Piaget, Jean and Inhelder, Barbel. The Child’s Conception of Space. London, Routledge & K. Paul,1956.
Weinberg, Steven. “The Search for Unity: Notes for a History of Quantum Field Theories”. Daedalus, Vol. 106, 1977.
Whitehead Alfred North. Science and the Modern World. New York: Pelican Mentor Books, 1925.
—. Process and Reality – An Essay in Cosmology. New York: The Free Press, Corrected edition, 1978.