With this article, I want to make a point on the main traditional presuppositions and personal assumptions I have presented so far concerning the meanings of the concepts of space and place.
The basic consideration on which I have founded my research on the concepts of space and place concerns the belief that concepts have not fixed meanings: they may change their senses, enlarge or reduce their denotative or connotative power in the course of history. This is especially evident when certain words and concepts acquire more technical meanings which surpass the original sense we had attributed them. So, for instance, a term like ‘atom’, which literally means ‘indivisible’, is still used by physicists and the common people to represent a certain physical configuration of matter even if we have realized that what we used to call ‘atom’ is everything but indivisible, thereby discarding the original sense of the word. The same holds for other important concepts like the concepts of space and place, which have continuously changed or revised their meanings during a couple of millennia of scholarly discussions on the spatial and/or placial nature of reality. We have seen that, in particular historical moments of great social and cultural changes, when men’s vision and understanding of the phenomena of reality changed, our understanding of the concepts of space and place also changed. We are currently living one of those crucial moments of paradigm changes and shifting visions in the history of mankind (see the articles Preliminary Notes, Place and Space: A Philosophical History and Space and Place: A Scientific History – Part I and Part II).
Another personal assumption which contrasts a traditional presupposition concerning spatial concepts, is that I reject the modes of thinking about space as a physical entity. I attribute the extensive character of reality (as well as its intensive character) to the concept of place in the revised sense that I’m arguing for in the pages and articles of this website. It means that every time I read the proposition ‘physical space’ in any context you may think of, or any time I hear someone speaking about space as if concrete bodies are immersed in it and move through it, I become suspicious. My suspect is that we are misplacing an abstract entity, space, for a concrete entity — the so-called physical continuum which sustains the existence of concrete things and bodies. I believe it is more fruitful to understand such extensive character of reality — which has to be thought of in seamless combination with intension, duration, and location — in terms of place, in which we are immersed and out of which we are created, rather than understanding it simply as a ‘physical space’, or describing it as ‘space’, in a metaphorical sense. The difference is that if we think about any surrounding situation, expanse or environment as a place, we necessarily have to consider the myriads of entities and processes which constitute that place as a situation, expanse or environment where processes occur. On the contrary, if we think about the same surrounding situation as space, we tend to consider the presence of entities (things, objects, or bodies as the occurrence of relations and processes) as if they are detached from the physical continuum in which those entities exist and behind which processes occur; therefore, we tend to forget that what actually defines the physical nature of a certain situation, its extensive and intensive characters (physical characters), cannot be disjointed from the temporal and local characters which are one thing with that which is extensive and/or intensive. That is: we tend to forget the relatedness between anything that exists (in that situation) understood as a whole where physical extension, duration and location cannot be disjointed, if not at the cost of some sort of extreme simplification of reality (this is what ‘abstraction’ means, after all). This sort of simplification of reality is what unconsciously happens when we reason in terms of space, which is a term that, by definition, conveys a sense of emptied extensiveness detached from what originates that extensiveness: this is what I have learned and experienced first-hand in my career as an architect (contemporary architects are especially focused on the concept of space, given that architecture is unanimously acknowledged as a discipline of space since the end of the XIX century) and as an observer of the phenomena of reality. This fact, this modality of abstraction we are seldom aware of, can be very deceitful in the analysis of phenomena if we overlook its abstracting (simplifying) power. In the end, what we are speaking about is the difference between concrete and abstract modes of thought, in respect of which concepts of place and space are representative terms. The ‘in which’ and the ‘out of which’ that I attribute to place reveal that place has intensive, extensive, temporal and local or locational characters that space has not. The Newtonian hypothesis concerning absolute space as an ambiguous entity which has both extensive and intensive characters has been rejected by contemporary Physics; as regards Einstein’s revision of Newton’s space in temporal terms — spacetime —, this is not the fundamental entity on which physicists rely on to envision the current spatial (or placial?) interpretation of reality: that fundamental entity is the field-concept (I’ve extendedly spoken about that in the historical article Space and Place: A Scientific History – Part II). To sum up this second assumption of mine concerning the concepts of space and place: I reject space as a physical entity, either we consider the three-dimensional neutral entity of Newtonian legacy — absolute space — or its upgraded version in the form of a tetra-dimensional entity — relative spacetime —, since I attribute to place the extensive as well as the intensive, temporal and locational characters of reality, all at once. Then, for me, space is just an abstract n-dimensional manifold that we attach to place ‘a posteriori’ in order to describe or explain those phenomena of reality which happen in place, or places, by abstracting certain characters (extension) to the detriment of others (intension, duration, location). Therefore, I consider space a concocted concept, a beautiful invention of the human mind, and not the actual background of our lives. No concrete thing really exists in space or moves across space; it’s just that concrete things exist in place and move from place to place. This means that any thing is always surrounded by other things, that is: the containing background of things is always made of things-as-places, which are connected to other things-as-places, within a relational hypothesis. In my opinion, it is a logical fallacy to speak about extensiveness as such and assign it a leading role in reconstructing our vision of reality, since extension is a property of things or bodies, and these things and bodies occupy places, they stand in place and move through places; they do not occupy space, or they do not stand in space, and they do not really move through space, since space, given its ideal nature, is only within our minds. That’s why I consider the concepts of absolute space or even space-time, limited concepts, even if they are highly effective concepts, not just within scientific, philosophical, or architectural circles; the limit is given by the fact that they are abstractions which do not clarify the fundamental cohesive nature of reality, splitting that nature into bits and pieces (extension/intension/duration/location) without a convincing hypothesis about their reunification.
Third assumption. So, we have come to another assumption that I have already talked about in some of the preceding articles: not only things occupy places, stand in a place or move from place to place; they can be conceived of as places themselves — the place of actualized processes which appear in the guise of particular things. From an ontological perspective, I believe places and physical existents are behind the same entity: they differ in thought. If I am not mistaken, at a fundamental physical level, this belief of mine is not far from the way contemporary physics understands the fundamentals of reality: it’s just that physicists speak about fields instead of places (see the article Space and Place: A Scientific History – Part Two). Yet, in the extended sense that I attribute to place, we could understand the fields of physics in the guise of physical states of place: at a fundamental physical level, all that exists are fields-as-places.
Fourth assumption. Coming back to the notion of space, apart from its rejection as a physical entity, I’m also quite sceptic about its excessive use as a figurative or metaphorical mode of language. This is not because such understanding of the term is wrong — after all, this means that space is an abstraction, which is precisely my viewpoint on the subject —, but because it does not go right to the point: what does the term space, or the idea behind it, really conceal? What does it lie behind space? In my opinion, understanding space as a figurative term or concept, does not answer that ontologically-relevant question. Ironically, instead of reinforcing the circularity between abstract and concrete modes of knowledge as the most appropriate mode of understanding reality, it seems the metaphorical use of the term space leaves suspended the important correlation between epistemological and ontological perspectives regarding the nature of that concept and the nature of reality. It is as if through the figurative use of the term space we are aware of that decisive correlation, but we never make a step forward to elucidate the nature of that correlation. In the end, it is as if we are contented with the generic possibility offered by language to stay in the middle ground between abstract and concrete modes of understanding reality without really questioning that ground and the correspondence of opposites which substantiate that ground; most of the time, this modality of understanding space leaves space itself as an unclarified notion. A good analogy for this elusive situation can be that of a bridge which starts from the bank of a river (the bank of abstraction) but we never see it reaching the opposite side (the bank of concreteness), because of the heavy fog in the middle; understanding space as a metaphorical notion is like living suspended on the bridge, immersed in the fog, without knowing the precise nature of that which the bridge really conjoins. I believe we can only elucidate the nature of space (and of place) if we address these highly relevant philosophical and physical questions: What is space as such? What is place as such? What is behind space and place? What is the nature of their relationship? What is the nature of knowledge? How does knowledge affect the nature of space and place or vice versa? In particular, I believe the metaphorical understanding of space fails to elucidate the concrete nature of reality where extensive, intensive, temporal, and local or locational values cannot be disjointed from each other. Neither can one value or character be considered more important and subsume other values or characters, as in the case of space, where we take extension (this is what space is in the end: pure extensiveness) as the most representative character of reality. This is properly the function of a figure of speech called ‘synecdoche’, where a part is taken as representative for the whole; the problem is that we tend to forget the power of that abstraction, and we often act as if one part (extension) is the whole of reality (ex/intension, duration and location), which is a logical fallacy. We live entangled in space with our minds before than with our bodies, and this may be a danger; as the narrator voice in the novel Middlemarch says: ‘… all of us, grave or light, get our thoughts entangled in metaphors, and act fatally on the strength of them.’  The risk is to misplace unicorns for another typology of horses, zebras or donkeys, belonging to the genus ‘Equus’ .
Another assumption behind my research is that if we want to elucidate the nature of space and place, or if we want to know what ultimately lies behind those terms, we must preserve the circularity that exists between our knowledge as subjects and the objects of our knowledge. Specifically, if we want to preserve that circularity, we should conceive of space and place as two correlate concepts from different domains — one ideal the other physical just like two integrated parts of a unique system — whose choral functioning discloses reality as one encompassing realm characterized by the fact of being seamlessly located, physically and temporally extended, and having a certain intensity (as regards the ‘location’ of an entity such characteristic has to be intended with respect to the parts which compose the whole of an entity and not as a ‘simple position’ abstracted from that entity, which can be either punctual or diffuse). Therefore, space and place shouldn’t be understood as concurrent concepts of the same reality, that is, space and place shouldn’t be understood as concepts belonging to the same physical domain, but they should be understood as correlate concepts — like in a sort of Yin-Yang relationship —, one, to begin with, concrete or physical, the other exclusively abstract or ideal.
It is of primary importance for us to understand that the difference between the concepts of space and place is one of substance (in the ontological sense: one concrete the other abstract) not one of degree (that is: one — space — including the other in virtue of a generic vs. particular character, or as if the dilemma space/place were a problem of scale). It is not enough for me the frequent objection that we can overlook the many differences between space and place, or that space (or place) ‘is just a term’; in this case, even if this means understanding space as an abstract entity to refer to something that we necessarily have to call, name or imagine to understand each other (language is intrinsically spatial/placial: using basic attributes and adverbs — of place! — like near/far, here/there, right/left, etc. we start building our immersive relationship to the physical world), space bypasses the troublesome correlation between the ontological and epistemological sides of the spatial/placial question, without which we cannot elucidate the nature of the concepts of space and place as such, and the nature of reality as well.
My scepticism on the frequent abuse or elusive use of space interpreted as an abstract term to describe concrete phenomena is also a move to contrast another traditional assumption concerning the concepts of space and place: that we take those concepts for granted, without inquiring into their meanings as such. However, we will say nothing new if we take traditional concepts to explain completely new phenomena like those we are experiencing in our contemporary epoch (the environmental question above all, but also globalization, which show the intimate link between politics, economics society and the environment, and to which concepts of space and place are deeply connected, not to mention the biological question related to the recent pandemic). We are currently experiencing a dramatically increasing gap of knowledge, habits and customs between our epoch and the previous ones, which, time after time, created, forged and modified the meanings of the concepts of space and place. It is properly in virtue of such increasing and almost unprecedented cultural and social gaps with respect to the past, that we have to rethink the concepts of space and place to have the appropriate theoretical tools to engage with completely new questions and problems (not just biological and environmental questions or the question of globalization mentioned above, but even, at more profound levels of knowledge, the physical question concerning the unification of the laws of nature — I mean the unification of Relativity and Quantum Mechanics within a new encompassing theory). Our modes of interpreting and understanding the multifarious phenomena of reality are different from those that people had at the epoch of Aristotle, Descartes, Newton, or, partly, Einstein; while the concepts of space and place that we still use to understand and describe either old or new phenomena are still heavily influenced by their visions. How can we fully understand and explain some characteristic phenomena of our times if the spatial or placial concepts we are using to describe them are outworn? It doesn’t make any sense trying to produce new forms of knowledge by relying on outworn concepts; we will just repeat what others have said before us — and better than us — in different ways; we will just enrich the deceitful category of formalism or linguistic exercises which make things and problems even more ambiguous and difficult to disentangle. Space and place are basic concepts not just for scientific, philosophical, social, political or architectural inquiries: those concepts are basic concepts for mankind because they are used in daily communication regardless of the context. This is the reason of their success and continuative use; and this is the reason why we should preserve their use reforming their meanings so that the old sense of those words can be included within wider perspectives, which are more appropriate to engage with the reality of our contemporary epoch. So, within the perspective that I’m working on, space maintains its natural/historical/literal character of extension, and it maintains the vastness of metaphorical possibilities; however, the notion of extension is attributed a mere abstract domain whenever it is conceived of in abstraction from intension, duration and location; this fact should be an antidote against the excessive metaphorical use of space preserving us from the error of misplacing that which is abstract — space — for that which is concrete — the physical reality-as place, which is seamlessly extended, located, temporalized and having a certain intensity. On a complementary side — the concrete side of place — the traditional characterization of place as location is also maintained although the very meaning of location is greatly expanded: location ought to be understood either as punctual or diffuse characteristic of bodies and things, given that what gives sense to a location is not the position of an entity with respect to an ideal or absolute frame of reference devoid of any physical meaning (this is the notion of simple location ‘substantiated’ by absolute space), but what gives sense to a location is the very physical existence of each entity, thing or body, — conceived of as a system of parts substantiated by processes — in relation with other entities. This means that whenever we speak of reality in terms of place or objects-place, 1] we are in a relational hypothesis; moreover, 2] analogously to premises of quantum mechanics with regard to the properties of entangled particles, it is accepted the image that two elements far apart can be the constituents of the same entangled whole or system, which determines the nature of that place as a system; this entangled whole, or system, either it is diffusely or punctually located, is physically extended other than temporally extended and having a non-zero intensity; it is this physical/temporal/local extension which constitutes the very essence of any entity-as-place; then location (the where of things), in/ex-tension (the what of things), and duration (the when of things) are the seamlessly associated characters which define the concrete existence of an entity-thing, which can also be thought of as an entity-place in virtue of these other considerations: 3] what sub-stantiates that entity-place, as a composed whole of in/ex-tension/location/duration, are processes; 4] by saying that processes substantiate any entity-as-place not only we unveil the correlation or complementarity between the abstract (processes) and the concrete (the entities-place as the concretization of processes), but 5] we also characterize and define the very nature of reality and its elements — entities and/or phenomena— as the evolutionary concretization of physicochemical, biological, social and symbolic processes, respectively; in this way, we can give a sense to the proposition ‘any entity is the place of processes’ specifying the nature of those processes, squaring the circle of reality in between processes, places and things (either abstract or concrete things). In a few words, the traditional sense of place we usually take for granted is complemented by physicochemical, biological, social and symbolic meanings which act in unison and influence each other defining the nature of reality as a place.
Gallery: On the different uses of the terms Space (spazio) and Place (luogo). See also the article The Feeling for Space and Place. Photos: Alessandro Calvi Rollino Architetto.
Now, lets’ put our focus on the concept of space only. For inquiring into its nature as such, we have said that we should initially suspend the traditional assumptions behind it, that is, space understood as a physical entity — which is tantamount to understanding space as a background or neutral container of events and happenings — and we should also beware of the excessive use of space as a metaphorical entity without contextualizing the burden of that metaphorical use; to do that we should ask the founding questions I have anticipated above: What is space as such? What is the relation between space and place? What is the relation between space and the way we have knowledge or experience of reality? Etc. Then, it is important to go back to the linguistic and historical origins of the concept of space, unveiling its main and basic different connotations as a simple extension — a one-dimensional distance either ‘physical’ or temporal —, an area — a two-dimensional region or territory —, a volumetric entity — a three-dimensional expanse —, which is the way space is traditionally assumed by people since the times of Newton, or as a volumetric entity in connection with time — a tetra-dimensional expanse —, as it is assumed after the works of Einstein and Minkowski. As an architect, I’m especially interested in the last two connotations of space, which we may term the ‘absolute’ and the ‘relative’, since they both depict space as a physical entity, rather than an ideal or abstract entity as it should be (absolute space, in a physical sense, was necessary for Newton to envision his Laws of Motion — I have spoken about that in the article Space and Place: A Scientific History – Part One; analogously, the explanation of spacetime can hardly escape any physical interpretation if the spacetime entity is subjected to the action of matter according to the premises of General Relativity). It was precisely such common and scholarly interpretations of space that I wanted to call into question when I started my inquiry into the meanings of space and place. At that time, I thought that we could eventually confirm and set our minds free from the traditional assumptions on the pseudo-physical or quasi-physical nature of space if we could answer the following question: does the three-dimensional extensive character of reality that we usually attribute to space emerge from our direct engagement with reality through the agency of our senses, or does it emerge from the abstract linguistic domain we are immersed into and specifically from the abstract domain of geometry?
More in detail, at the very beginning, I wanted to answer the following question: having identified Cartesian geometry and space, and Newtonian physics and space as some apical moments in the history of human understanding, do such now-traditional spatial modes of thinking about reality — as a volumetric, neutral and immersive space — come before or after the Cartesian and Newtonian innovations? Could it be that the two relevant assumptions about space that I wanted to call into question — space understood as a physical entity and the redundant use of space as a metaphorical entity — had the same genesis? My initial hypothesis was that only after Cartesian geometry and Newtonian space were invented (I believe the two moments are intimately connected) could our minds envision space as a neutral container or three-dimensional object (and, centuries later, as a tetra-dimensional object) attached to reality; and, as a consequence, only after those inventions could we envision space as a metaphorical tool (in a 3D sense) in-between concrete and abstract domains. Before that date, only some sporadic minds or small groups of highly trained people could probably do that (e.g. the Atomists), this fact being an indication that the level of abstraction required to understand the nature of reality as space is very high and, consequently, it is hazardous to speak of ‘intuitive space’ or ‘background space’ as if they were ‘natural’ entities (biological?) directly connected to or depending on to the world of physical phenomena (here I join with James J. Gibson’s hypothesis: ‘…The doctrine that we could not perceive the world around us unless we already had the concept of space is nonsense. It is quite the other way around: We could not conceive of empty space unless we could see the ground under our feet and the sky above…’).  What interested me was the diffusion of spatial/placial concepts at social levels rather than the single act of a genius, or small groups of people ahead of (out of?) their times; for the sake of argument, we might hypothesize that Anaximander or the Atomists, through their abstract concepts — ‘apeiron’ and ‘to kenon’, respectively — could have glimpsed into a spatial conceptualization of reality very similar to the modern conception of space; however, from the classical antiquity of the Greco-Roman World to the Late Middle Ages, what prevailed was the very physical (and metaphysically active) concept of place — ‘topos’ — defined by Aristotle. My initial belief was that, by the time of its diffusion in common parlance, and with the time passing by, space was respectively understood as a term indicating a simple distance — 1D — or a region on the earth or in the sky — 2D —, without necessarily implying that volumetric understanding of the term — 3D — that we, modern people, always take for granted even when we read ancient texts, improperly attributing old terms modern meanings. What we have learned from history is that ancient people looked at the world as a plenum (of things and phenomena) rather than as a void; that’s why Aristotle’s physical/placial model triumphed over the alternative ‘spatial’ model proposed by the Atomists (I define Aristotle’s model a ‘placial model’ to point out the encompassing value of the concept of place — ‘topos’ — which was as fundamental as the concept of absolute space was for Newton to devise his cosmological model; in both cases, physical and metaphysical connotations reinforced each other even if the focus is always put on the physical connotation). These considerations took me to embrace the hypothesis that only after Newton reified geometrical space, transforming an abstract entity — Cartesian space — into a concrete entity — absolute space as the transparent, rarefied neutral container infinitely extended along the three axes/dimensions (x, y, z) —, could we envision space as a physical entity, opening up, at the same time, the possibility to understand space as a metaphorical entity, especially for those who were, and still are a bit sceptical about the Newtonian invention. This is now for me another assumption behind my research on space and place.
This means that, for me, it is highly plausible that before those Cartesian and Newtonian innovations, people and things moved from place to place or rested in their respective places (à la Aristotle); after that, people and things started to move through space or rested in it (à la Newton, which is now the traditional view). The situation described is the same, but the new way of understanding and describing that situation — that is the new way of understanding reality and its laws — radically changed. It is also in virtue of those Cartesian and Newtonian innovations that man’s overall vision of the world radically changed. I firmly believe that no Scientific Revolution could have ever been formalized and no Industrial Revolution could have ever started without the invention of ‘physical space’ and its capillary diffusion in the mind of people (engineers, technicians, entrepreneurs and business people were the first to understand the infinite possibilities opened up by the ‘new’ concept of space; here, the deep connection between the modern notion of space and the sociocultural processes which led to the rise of capitalism and globalization defines another field of spatial/placial investigation that I will deal with in future articles). Of course, this is a simplification of complex and interlacing historical social and cultural processes that lasted many centuries; as I already had the occasion to say in previous articles, in this long process concerning the placial/spatial understanding of the world there were other topical moments (starting from the immediate criticism to the Aristotelian concept ‘topos‘, the application of trigonometry to astronomy, the discovery of perspective, etc.) which concurred to the formalization of the modern concept of space. Therefore, we have to understand this simplification in the specific sense hypothesized by Julian Barbour: apical moments — watersheds is the precise term used by Barbour —  which sum up and formalize man’s shifting vision of reality (see the introduction of the article Space and Place: A Scientific History – Part One). It is our understanding of reality as a physical space, where the character of immaterial extension was severed from and triumphant over other characters (materiality, temporality, locality) which took us to the present situation. We have inherited many problems from that simplified, abstract vision of reality: above all — and this is just the tip of the iceberg — the environmental question which is intimately connected to the modern modes of production of goods and consumption of natural resources; those modes could be imagined and implemented because reality (Nature) was understood as a neutral space, detached from the processes in it, which is a logical nonsense I argue against by proposing a different vision of the concepts of space and place, through which exposing the processual, systemic, relational, evolutionary and complementary characters of reality understood as an encompassing place. Concepts are a prime motor of change: only if we are able to express our different visions of reality employing new concepts or old concepts, revisited, which supersede old meanings, can we effectively change reality.
Apart from or in addition to the historical analyses of the kind I have presented through the works of Max Jammer, Edward Casey, Julian Barbour, or Steven Weinberg and others, is there a way to prove the hypothesis that space — I mean space as we commonly understand it now, that is, as a volumetric entity in which we believe things move and events occur — was a concept concocted after Cartesian geometry was invented and Newtonian innovations introduced? Can this alternative way unveil the correlations between the geometrical, the physical and the metaphorical genesis of space understood as a three-dimensional (or tetra-dimensional) entity? At the time when I began to investigate with constancy into questions of space and place, these and other questions I left slumbering for many months within my mind while putting together the opinions of those who — like me — believed that space was just one of the smartest inventions of mankind; and while I was deepening my knowledge on space and place by reading historically-based texts, I began to think that a possible way to test those hypotheses could be the analysis of some ancient texts to see how the terms ‘space’ or ‘place’ (i.e. their equivalent Latin or Greek forms) were used by the original authors and then translated. So this article and some of the personal assumptions and traditional presuppositions concerning the concepts of space and place I have mentioned, can also be considered as the prelude to the next article — Concepts of Space in Vitruvius  — in which I will present a sort of philological research based on the analysis of Vitruvius’s text De Architectura, which I began time ago with the precise scope to inquire into the presuppositions concerning the concept of space (before all, physical space, or space understood as a three-dimensional immersive notion, and the related understanding of space as a metaphorical concept, in the most encompassing sense deriving from the notion of extensiveness as such).
 Concerning my interpretation of the difference and continuity between the notions ‘extension’ and ‘intension’ see the article Place, Space, and the Fabric of Reality, especially Images 6 and 7.
 George Eliot, Middlemarch (New York: Barnes and Nobles Classics, 1996), 80.
 James J. Gibson, The Ecological Approach to Visual Perception (New York: Psychology Press Classic Editions, 2015), xv-xvi.
 Julian B. Barbour, The Discovery of Dynamics (New York: Oxford University Press Inc., 2001), 13.
 Maybe, it is worthwhile noting that I made this type of analysis on Vitruvius’s text De Architectura after reading books like The Fate of Place by E. Casey, Concepts of Space by M. Jammer, Concepts of Space and Time by M. Capek,and others historically-based texts — see the references in my paper From Space to Place, which dates back to 2014 ( but before reading J. Barbour’s The Discovery of Dynamics). This means that I already was aware that space (and place) had different interpretations according to the different epochs, but to establish which interpretation is correct or more plausible than another is still another question; this type of study that I’m going to present in the article Concepts of Space in Vitruvius could be another option to inquire into the different interpretations of the concept of space.
Barbour, Julian B. The Discovery of Dynamics: A Study from a Machian Point of View of the Discovery and the Structure of Dynamical Theories. New York: Oxford University Press Inc., 2001.
Eliot, George. Middlemarch. New York: Barnes and Nobles Classics, 1996.
Gibson, James J. The Ecological Approach to Visual Perception. New York: Psychology Press Classic Editions, 2015.