Perception, Reason and Substance (2019)

Perception, Reason and Substance

Abstract

This discussion presents a view of relations between materiality and self-awareness that I have already expressed in the course of other enquiries. Here the argument is focussed more specifically and precisely on how these relations should be understood, and, in particular, on how sensory perception should be seen in the light of a more expansive view of perception that includes abstract thought such as reflection, calculation, judgement and logical reasoning. At the heart of the argument a conception of sensory perception as the realization of substance is opposed to alternatives that conceive it as being itself a substance, either as a neutral substance that is physical when seen in one way and sensory when seen in another, or as an immaterial substance that is contrasted with materiality. 

   I develop this approach into a monistic theory which explores the underlying connections between sensory perception and abstract reasoning. In particular, these connections are elucidated so that we can see how the substantial form of reflective life – a life that is valued in itself – is adequately expressed in subtle interactions between the different but closely related modes of perception.  In conclusion, I draw the main elements of the argument together in an account of the coherence of phenomena in terms of intersubjectivity and our participation in a common form of life.  

Sensory Perception as the Source of Character in Phenomena; Refutation of Neutral Monism and Hylemorphic Dualism

Depth of experience lies in cumulative acts of sensory perception along with thought and reflection. In this connection, the sense of a soul or inner identity arises (primarily) out of the multiplicity of acts of sensory perception that are necessary to the realization of things and determine their constitution. For example, my inner identification with a certain piece of music, or a certain painting, arises out of its realization in an act of sensory perception that is informed by my experiential history. Furthermore, the interdependence of sensory perception and the object is the reason why phenomena are realized only in recognition. This in turn creates the possibility of an intelligible world to which realization of the object belongs, and an intelligible world is the essential context in which phenomena are discovered, and in which the laws that govern them and the nature of their elements are also discovered (these laws and elements are laws and elements of phenomena, and not laws and elements of a realm that is separate from life and sentience). Therefore, all of science is the study of phenomena, and without the act of sensory perception that determines the constitution of physical objects there are no phenomena, only the incipient objects that are their physical basis.

   This points to an underlying connection between (1) the relation between the physical object and the act of sensory perception as generated by a history of thought and experience, (2) the mutual involvement of materiality and self-awareness as the source of phenomena, and (3) the identification of this mutual involvement with an understanding of all of the physical structures that lie within phenomena. Without recognition and the sense of oneself and an intelligible world there is neither sensory perception nor physical object as a fully realized phenomenon, and this puts the mutual involvement of materiality and self-awareness at the heart of all phenomena. On the other hand, inner experience is, in this connection, not itself an object but rather the term in a relation with materiality for the realization of an object. By definition, the realization and the experiential history that informs it are not physical and cannot be understood in physical terms, such as activity in the brain.

    This implies a subliminal knowledge in empirical knowledge itself. To see a cup as a vessel for drinking tea or coffee is to turn materiality (or the incipient object) into an object that is determined by the experiential history of a sentient being, which implies that a kind of self-knowledge is concealed within the constitution of the physical object. I could not see a cup as a vessel for drinking tea or coffee without seeing that object as significant to my experience of life in the way that I do. So, while I cannot see what lies within the act of perception itself, a form of self-knowledge is involved in my seeing the cup as a certain kind of vessel. Conversely, the incipient object is both fully physical in accordance with the laws of nature, and characterless; but, in addition to being at one with the physical aspect of the object, the incipient object is inclined towards life and sentience.

   We can see that the incipient object must accord physically with the physical object, since the act of perception in itself does not (for example) make a cup solid and solidity is necessary in a vessel for drinking tea or coffee. And if the incipient object were not inclined towards life and sentience, both in immediate experience and as a continuous process that is independent of actual experience, then neither I myself nor my experience of a cup with a cup-like character would be possible.            

   Correspondingly, the physicality of the incipient object can be inferred but not perceived, since its being perceived makes it phenomenal and, in this connection, no longer incipient. Furthermore, it will be clear that in this metaphysical account the physical object is not an appearance that is derived from something more fundamental, something that might be considered a thing-in-itself. Rather, the physical object is a realization of what, prior to this realization, is only incipient. What makes the physical object problematic is the character it is given by an act of sensory perception, as this is variable, and often widely variable – both in different sentient beings and in the same sentient being at different times. The essence of the object is impossible to define in simple terms, as this is determined by the influence upon its character of the past experience of the perceiver. This turns the idea of a thing-in-itself on its head; the essence lies not in the incipient object but in its realization as a phenomenon in the sensory perception of a sentient being. 

   With respect to this point, I should mention that materiality and self-awareness are not united by their derivation from some common and otherwise neutral source. Rather, the physical object is realized from the incipient object by an act of sensory perception, and in the mutual involvement between materiality and self-awareness that gives the phenomenon its character there is no need for any further unifying entity or influence. There is nothing in which they can be united as complementary manifestations. For example, sensation might appear to provide the basis for a theoretical integration of perception and the physical elements of a physical object, but this depends upon the idea of neutrality with respect to sensation. In this connection, sensation must be conceived as having no subject, since the volition and impulses of a subject exclude neutrality. 

   Such a view is not supported by what we know sensation to be. Consider the following experience: a person is walking home in the dark and becomes aware that she is being followed. She is increasingly afraid and this leads to her starting to tremble; here the sensation of trembling can hardly be said to exist in the absence of a subject, as it is an expression of somebody’s emotional state. Since there are countless such experiences in which emotional states can involve sensation, those of pleasure, desire, remorse, anxiety, relief, anticipation, disappointment and many others, it is impossible to regard sensation as being neutral in the required sense. This is just one way of showing that to speak of sensation as having no subject is to wrench the idea of sensation out of the context that gives it meaning. All sensation is an effect on some existing state of feeling or emotion in a sentient being. To offer an explicit formulation that excludes the possibility of neutrality: the realization of phenomena lies simply in a subliminally self-aware arousal of past experience acting upon an incipient object that is appropriately physical and inclined towards sentience.  

   In support of the idea that the incipient object is necessarily inclined towards life and sentience, I can appeal to the nature of physical modes by means of which the physical object is realized. Thus, in addition to being physical in accordance with the laws of nature, many physical modes are also media for sensory perception. The history of past experience that determines the constitution of a physical object requires from the incipient object certain media that will make it receptive to the shaping powers of sensory perception.

   To make use of an earlier argument (Nelson, 2018), light does not become a medium of sensory perception when sentient beings emerge; the physical basis for light must be present in the incipient object long before sentient life appears, and light is by nature (among other things) a medium of sensory perception. Hence there are physical modes that are also media of sensory perception – like light, space, time, movement, shape, size, contour, volume, energy, temperature, weight, density, sound, touch, taste and smell. These and many other physical modes are media of sensory perception long before there are any sentient beings to experience them, and this strongly suggests an inclination towards life and sentience in the incipient object or, to put it another way, a mutual involvement of materiality and self-awareness.

   Thus, from this basic identification of physical modes with media of sensory perception, we can see that the physical object is minimally realized as a complex of such media, as, for example, when a sunlit meadow is realized as a complex of space, time, light, size (including proportions of landscape and sky and various forms within them), contour, movement (or its absence), volume and temperature, along with other possibilities like sound and smell. This organization of the media reflects how the incipient object as material is dynamically transformed by the act of sensory perception, and the intelligibility of the physical object is equally reflected in the effect of past experience upon its significance. Thus, intelligibility depends upon a co-ordination of the media that organize the physical form of the object with the influence of past experience that gives it character. 

   The unity of mind and body is in the physical object, which has a certain character and therefore integrates the material with the abstractive and aesthetical. Sensory perception is of a physical object, and therefore of the material, and it does not make much sense to speak of perception itself as a substance. Substance is in the object perceived, and lies in the mutual involvement of materiality and self-awareness extending subliminally over the whole experience of an organism. Thus, there is no dualism beyond the necessary duality of experience and an object of experience, and the experience is immaterial in the sense that being of the material it cannot be otherwise. The perception of a bicycle is no more physical than the memory, imagining or the assessment of a bicycle; it is a way of realizing the character of an object. 

   At the same time, the perception of an object has a psychological significance for the perceiver who realizes it, but neither does this create a dualistic opposition of inner experience and physical object. Since the character of the object is created by psychological inclinations that are shaped by inner experience, the psychological significance of the object for the perceiver (as an act of sensory perception) lies in its integration of the material with the abstractive and aesthetical. Hence, apart from a particular history of sensory experience, reflection, inner experience (such as memory and imagination) and psychology in general, there is no separate sphere in the perceiver that affects the character of the object. From this point of view, the object can be understood in terms of materiality and its incorporation into a self-aware realization, in which the experiential and psychological history of a sentient being is subliminally active. To the perceiver, a particular bicycle might be realized as a pleasing vehicle for exploring the surrounding countryside, and its significance will lie for him or her in its possessing this character.

   This argument makes no reference to qualia and the irreducibility of inner experience to physical processes. Rather, it is directly concerned with the fundamental relation of sensory perception to phenomena, and therefore with the constitution of both the physical object and the nature of experience. In this connection, it shows how sensory perception transforms the material into a physical object with a character that is significant to the perceiver. Clearly, a psychological action of this kind cannot be converted into a relation between different kinds of material or physical object. Consequently, if the act of sensory perception were to be interpreted as physical, like a certain activity in the brain, then this physical object (or physical event) would also be in the relation of sensory perception to phenomena. The character of a cup (for example) would be realized in sensory perception as a vessel for drinking tea of coffee while the cerebral activity (supposing it to be directly observed) would be realized in sensory perception as a function of seeing the cup (this being its significance to the perceiver). Regardless of how the act of perception might be assumed to be physical, the fundamental relation cannot be shaken off, it arises from the centrality of self-awareness to the constitution of any physical object. 

   As an object of contemplation, the bicycle could have many kinds of significance, but this does not imply dualism either. Contemplation, analysis, imagination, recollection, abstract thought and other higher level mental activities are continuous with sensory perception – for example, reflection, analysis and intuition are always interwoven with memory and imagination, and the latter are continuous with sensory perception. Correspondingly, all of these mental activities influence the realization of the physical object in sensory perception (what we experience in sensory perception is obviously influenced by how we might be preoccupied with an object). 

   Moreover, when I say that substance is not in the act of sensory perception but in the object perceived I refer also to perception of oneself and other people, and sensory perception is a way in which we are interested in a person’s substance. In this connection, the perception of oneself (self-awareness) that pervades experience is the primary distinction, but here also substance lies not in the perception but in the object that is shaped by the subject’s experiential history. All that is relevant to character and substance can be seen in relation to the experience of an object; the experience arises out of sensory perception, which is of an object. This represents a unity that lies within the possibility of phenomena in general, and this unity is at the heart of all further developments of experience and the objects of experience. The intricate web of interactions between sensory perception, phenomena, and the ever-changing substance of a person represents a unity in the identity of a sentient being and is incompatible with a categorical dualism of mind and body. This argument shows that sensory perception realizes the material as a physical object that has a character for the subject (mind is defined by its transforming action on the material), while the material is given a certain character by sensory perception (body is defined by its mental realization as a physical object).

   In the interests of clarity, I should expand these remarks in one respect, for though substance and character lie in the object, we have seen that the act of sensory perception gives the physical object its substance by drawing upon the experiential history of a sentient being. This means that any particular realization of the physical object will be influenced by the substance of innumerable physical objects realized in earlier experiences. While it may not itself possess substance, sensory perception does not simply produce an image of the physical object but is the vehicle for substance that might come from anywhere in the past experience of an organism. So, without themselves being substance, numerous acts of sensory perception are (subliminally) instrumental to the complex realization of substance in the physical object (for example, a cup as a vessel for drinking tea or coffee with a particular aesthetic quality and other kinds of significance to the perceiver). Because substance lies in the object, and the act of sensory perception is intimately involved in its constitution as a realization of substance, when considering phenomena we can speak of an integration of mind and body that avoids dualism.

   As well as avoiding dualism this particular point enables us to see the shortcomings of Aristotle’s hylemorphic dualism, the theory that the physical object is a compound, or composite, of matter and form, and that form is substantial in giving the object its essence and identity (Oderberg 2005). Aristotle’s dualism sees the substantial form of a person as lying in his or her being a rational creature, a substance that is not shared by other animals and is to this extent unique to human beings. Therefore, the soul of a person lies in being matter that is organized so that body and mind are integrated in experience and behaviour, and also separate in so far as mind involves certain capacities of its own, such as the power of conceptual and abstract thought. This power is regarded by Aristotle as independent of matter, since a concept like freedom or duty does not owe its meaning and significance to any material particular, and, given the pre-eminence of this power as a personal attribute, the soul lies in a rationality to which the other attributes of a person are subservient. Rationality is sovereign in the sense that, in a rational being, all inclinations should be subject to the control that is exerted upon them by reason.

   There are two significant ways in which my conception of sensory knowledge and its relation to the physical object is opposed to the theory of hylemorphic dualism; one is concerned with the separation of mind and body that gives a unique form to human life, and, within this, the other is concerned with the idea that conceptual and abstract thought give sovereignty to reason over all attributes of a rational being. With respect to the first of these, we now know that just as there is an organ for the absorption and distribution of oxygen so there is an organ for the intellect, namely the brain. Thus, the idea that in some things the mind and body function separately is, in the simplest terms of a direct relation between the two, impossible to accept. We know, for example, that the structure of the brain is affected by experience and that this includes modifications that are due to higher level thought and reflection. Moreover, it is well established that damage to the brain can have extremely adverse effects upon the intellect, as in loss of memory and cognitive function. (This does not mean that intellectual activity is the same thing as physical changes or activity in the brain (Nelson 2018), any more than the absorption of oxygen into the body is the same thing as the lung, which, no doubt, also changes in structure with use.)

   Still on the matter of whether the mind and body ever function separately, such a possibility is not confirmed by the account that I have given of sensory perception and the physical object. In this connection, we have seen that, in a realization of the latter, the act of sensory perception engages not only with the incipient object from which it is separate, but also with a past history in which the physical object has, perhaps, already been realized by sensory perception and reflection on innumerable occasions. This means that mind and body cannot function separately in sensory perception, because realization of the physical object depends upon the mutual involvement of such perception and the incipient object.

   When this dependence is referred to modes of experience that are not directly concerned with sensory perception there is also a constraint upon the possibility that the mind and body can function separately. In conceptual and abstract thought, such as the theory of Aristotle with which we are concerned, or our being concerned with it, there is necessarily no direct engagement with an incipient object that realizes the physical object. However, there is an indirect engagement with a past history in which the physical object has been realized by sensory perception. Unless it were informed by such experience it would be impossible to formulate any ideas about rationality and its significance to the substantial form of a person, since in that case there would be no experience upon which to base any ideas about it. Ideas about relations between mind and body depend upon what experience shows us about the relation, and experience depends upon the past history of sensory perception and the physical acting interdependently. The same must be true of our exercise of conceptual and abstract thought of any kind.  

    Here it is appropriate to elucidate something about the part that is played in sensory perception by past experience of reflective thought. In relations between the two it is obvious not only that abstract ideas inform our perceptions (as when we see a cup as a vessel for drinking tea of coffee) and thereby create a basis for reflection, but also that refection and abstract reasoning play a vital part in the influence of past experience upon sensory perception. This is familiar in the way, for example, perception of a machine is affected by finding out something about it. A seemingly impressive motor car will look quite different to us when we learn that it functions badly. Similarly, a person who appears to be urbane and amusing can look quite different when we have learned that his amusing persona is sometimes assumed in order to make fun of oneself.

   Turning to the second objection to Aristotle’s theory: if conceptual and abstract thought actually gave sovereignty over all other attributes to the rationality of a rational being then we would be justified in thinking that we must be predominantly rational, and this idea has serious consequences. One is that a reasonable status quo, in which the majority lead seemingly stable and fulfilling lives will be justified by the assumption that social and political harmony may be explained by the sovereignty of reason in a rational being such as ourselves. When things are going smoothly, the criticism of rationality is not a high priority, and abstract thought and reason are routinely employed in order to serve ends that are far from rational, and ends that are far from good. Moreover, we are much more likely to become aware of our irrationality when there is a crisis, and when the crisis has passed we can if we wish go back to believing in the sovereignty of our abstract thought and reason.

     Consider some of the ‘rational’ beliefs of Aristotle himself, such as the belief that slaves are inferior people, or that in human reproduction the woman is merely a vessel for characteristics that are provided by the man. These may reflect an acceptance of received ideas and were open to a considerable degree of rational investigation. Even the convictions of a great philosopher are not necessarily guided by, or even subject to, strict rational scrutiny, and in most philosophy, including Aristotle’s conception of the sovereignty of reason, inconvenient difficulties are ignored. Examples of reason being used to ends that are far from good can be seen at any time, as in the use of abstract thought and reason by politicians and their avaricious and influential allies to embezzle the nation’s wealth. It is fair to say that in isolation from all other qualities, abstract thought and reason are morally neutral and employed equally as resources for good and evil, and therefore to regard them as sovereign over all other personal attributes is highly contentious. The fact that they are more refined and extensive in a certain kind of being does not in itself imply that they must be given sovereignty or must uniquely represent the form of that being. The most that we can claim is that reason in concert with other attributes might be regarded as sovereign in a certain kind of being. It is a matter of dispute whether it is called a rational being, or another kind of being that possesses the powers of abstract thought and reason.   

   The basic relation in sensory perception of the physical object is not transformed but only extended in the relation of reflecting upon ideas, making conscious judgements or calculations, or engaging in logical reasoning. These too are kinds of perception, and the perception of something is no more a substance than the act of sensory perception. To regard the judgement that I should do more exercise as more than a perception and equate it with an immaterial substance is not obviously justified. Just as the act of sensory perception is the realization of a physical object and determines its substance, but is not itself a substance, so a judgement or calculation is a kind of perception that realizes a physical or psychological possibility. In neither is there an immaterial substance involved because the judgement or calculation is a counterpart of the act of sensory perception and not the physical object. It is true that the person is changed by judgements and logical reasoning – and often simply by having them – but this does not distinguish them from sensory perception and the realization of physical objects.

   That abstract thought is not itself a substance, but rather, like sensory perception, a way of realizing the substantial form of a physical (or psychological) object can easily be shown. Suppose that a person sees a square of evenly spaced cones and that this represents the realization of a substance in a certain physical arrangement. Then she counts the cones on one side of the square, which is four, and multiplies that by itself and so calculates that there are sixteen cones. By calculation, the realization of a harmonious arrangement of objects in sensory perception is turned into a realization of the number of these objects. Furthermore, this affinity between sensory perception and abstract thought can be established more closely in relation to the nature of each. So, it might be considered that calculating the number of cones is a significant cognitive progression, since calculation tells us more than mere sensory perception about the square of evenly spaced cones. However, this is true only from one point of view; the square might be interestingly tilted and the cones subtly varied in size and richly and harmoniously coloured. Simply as a sensory experience the square is abstract, and just as we see a cup as a vessel for drinking tea or coffee we will see the square as abstract, perhaps as an intriguing work of art. Because the sensory perception itself, even before any judgement or calculation is made, is both concrete and abstract, this realization of the object might be far richer and more complex than the calculation of how many cones there are in the square. By no means does abstract thought in itself cover all of the ways in which a physical object can be more complex and interesting (even a calculation of how many atoms there are in all of the cones together might well be less complex and interesting than the bare visual experience of seeing the square). 

   What is true of calculation is equally true of other forms of abstract thought. The judgement that I should do more exercise is not a substance but, rather, a particular way in which a substantial form, myself, is realized in my imagination, while the intention to do more exercise is a more purposeful way in which the same substantial form is realized. In this case, we can see that abstract thought is frequently entangled with intention, both as a consequence and as an anticipation – making a judgement can have hidden intentions behind it. To follow the examples of Aristotle and hylemorphic dualism, and regard these forms of abstract thought as immaterial, is to fall prey to a category mistake. Realization of the physical object, either as a sensory perception or as the subject of a calculation, judgement or of logical reasoning, is not itself a substantial form that can be opposed to what is material. The distinction between material and immaterial substance does not apply to the ways in which a physical object can be realized, any more than it would apply to the realization of a psychological state, such as a sense of relief or an inclination to play the piano or listen to Bach.

   It is true that the substantial form that is myself is constantly affected, and in some way altered, by forms of abstract thought and the different ways in which they realize phenomena (including myself), but the substance lies in me and not in those forms. Hence there is no reason to believe that a being that possesses some non-sensory ways of realizing and altering itself and the world is any more immaterial than one that doesn’t possess them. Hylemorphic dualism relies on an opposition of the abstract to the corporeal that makes abstract thought synonymous with immateriality when, in this case, it is only synonymous with a realization of the physical object that is not an act of sensory perception.

Abstract Thought in Perception and Reflection; Interdependence of Reason and Imagination in the Substantial Form of Reflective Life

Rather than define a person as a rational being and regard this as its substantial form we should examine the relationship between reason and a sentient life in which reflection in which ideas, calculation, judgement and logical reasoning play a central role. However powerful the evidence of reason and however much it distinguishes a particular form of life from other sentient lives, we cannot simply assume it to be the defining characteristic of that form, or to be sovereign over all other qualities and attributes. Thus, in order to question these assumptions, we could start by considering how different kinds of abstract thought are related to each other, as a way of seeing what binds them together in the experience of a sentient being that is characteristically rational.

    When the hylemorphic dualist defines a person as pre-eminently a rational being he distinguishes one type of being on the grounds that it is able to control its life in ways that are not open to other animals, and, in this respect, he implicitly refers to the sense of purpose that guides behaviour. Therefore, he is not talking about a mere aptitude that can range from calculating the size of a galaxy to guessing the motives of another person, his concern is with abstract thought as a means of organizing a life that is valued in itself. In this connection, the close relations between reflection, judgement, calculation and other expressions of abstract thought are highly relevant, and reason is significant, above all, in enabling a reflective being to determine its own life and experience. Whatever the extent to which some are able to develop the use of reason in certain ways, such intellectual ability, does not define the nature of reason in the life of a reflective being. Rather, it is in the characteristic life of people in general, in its interpersonal and intersubjective constitution, that we see how human being can take a particular form, since the substantial form of a species cannot be defined in terms of the specialized skills of a small number of its members. In this respect, abstract thought can be seen as essentially a capacity for refining and extending the already abstract discernment that lies naturally in the sensory perception – and related emotional experience – of other animals, many of which are themselves capable of calculation and reflective judgement.

   This particular connection between abstract thought and sensory perception implies that reason does not typically act autonomously but is interwoven with reflectiveness in human actions, as we have already seen in the commonplace entanglement of reflective judgement with intentions. Therefore, it is misleading to imagine that a person is primarily a rational being whose true nature (or substantial form) is threatened and sometimes unsettled, or even ruined, by impulses and feelings. It is far more reasonable to see what is human as a life that is reflected upon because it is valued in itself and, for this reason, examined in many ways. Such a view justifies regarding a person as a reflective being and accepting this as his or her substantial form. Then reason becomes an instrumental development of sensory perception, and is stimulated in various ways and to varying degrees by the aims of a community or civilization. Reflective life can be enhanced and protected in many ways by reason, but reason does not define it, and it can easily be dominated by inclinations that are untouched by reason or decidedly irrational. 

   This conception departs from the theory that human life is defined by a conflict between reason and feeling, in which a sovereign capacity for abstract thought holds sway, or strives to do so, over the lawless inclinations of natural feelings and impulses. The capacities and inclinations of a person are rarely seen in this way in our actual experience. In spite of those occasions when we act unreflectingly on impulse, the inclinations of a reflective being are characteristically affected by the abstract thought that lies in their past, both in sensory experience and in reflection. We know that conflict between individuals and communities generally occurs when principles are violated or ignored, or in relation to ambition, rivalry and conquest, and in other situations where strong personal interest is involved. Thus, in most cases reason and abstract thought play a central role in behaviour on both sides of a conflict; reason and feeling being intertwined in ways that make it difficult to speak of reason as a sovereign influence over attributes that are considered to be relatively primitive.

   In experience of inner conflict there might be questions of overcoming strong inclinations that are against one’s own interests or related to actions that trouble conscience or sense of oneself or image, and these are also matters that involve abstract thought on both sides of the conflict. They are not the suppression of feeling by a sovereign reason, and it is likely to be very rare for somebody to attempt to overcome a strong feeling of any kind simply because that feeling is not rational. Furthermore, this raises questions concerning the sovereignty of reason over a grasp of the things about which it is considered to be worthwhile to reason. For example, sensitivity to the wellbeing of others, say of children to whom responsibility is due, or fellow citizens, or people in general makes demands upon reason, but equally it makes demands upon care and observation, and these are not in themselves expressions of abstract thought in the sense of ideas, judgement, calculation and logical reasoning. In much of our experience, reason and observation are intertwined, and it is impossible to determine whether one of them is sovereign. It is not difficult to see that reason becomes ineffective, or even destructive, if it is allowed to operate on the basis of careless observation. So, while the clear formulation of ideas, judgement, accurate calculation and logical reasoning are essential to constructive action, these abstract processes do not belong to an autonomous realm but are usually interwoven with the experience, observation and self-awareness which reason can lead and to which it must also be responsive. Hence a subtle interplay between abstract reasoning and sensory experience is familiar to us in the anticipatory feeling that something is the case before we make the judgement that it is so (as might occur in reading and trying to interpret a poem).

   The expression of intellect in a work of art is similar to seeing into the motives and behaviour of a person. In neither is insight simply a matter of abstract thought, though insight depends upon our capacity for this kind of thinking. For this kind of thinking itself depends upon an imaginative perception of the work or person that enables the interpreter to form a true sense of what it is that reason is given to analyse. Moreover, in both cases abstract thought and imagination are in constant interaction; we do not form in imagination a clear conception of the subject matter and then operate on this with the resources of analytical reason. Rather, the process of understanding is one in which the two faculties constantly work in concert with each other so as to gradually achieve greater clarity. Abstract thought without imaginative reach does not result in intellect, at least not in the sense that we can equate with the substantial form of a work of art or a person. In the example that follows a powerful expression of intellect includes a subtle interaction of abstract thought and imagination in which attention is drawn, in particular, to memory, the inner life of sensory perception and language. Thus, I will attempt to show how the first of Hamlet’s soliloquies exemplifies the intellect as an expression of the substantial form of human life.

Hamlet

            O, that this too too solid flesh would melt,

            Thaw, and resolve itself into a dew!

            Or that the Everlasting had not fix’d

            His canon ‘gainst self-slaughter!  O God!  God!

            How weary, stale, flat, and unprofitable,

            Seem to me all the uses of this world!

            Fie on’t!  Ah, fie!  ’tis an unweeded garden,

            That grows to seed; things rank and gross in nature

            Possess it merely.  That it should come to this!

            But two months dead!  Nay, not so much, not two,

            So excellent a King that was to this 

Hyperion to a satyr; so loving to my mother,

            That he might not beteem the winds of heaven 

            Visit her face too roughly.  Heaven and earth!

            Must I remember?  Why, she would hang on him

            As if increase of appetite had grown

            By what it fed on; and yet, within a month –

Let me not think on’t.  Frailty, thy name is woman! –

            A little month, or ere those shoes were old

            With which she followed my poor father’s body,

            Like Niobe, all tears – why she, even she –

            O God!  a beast that wants discourse of reason

Would have mourned longer – married to my uncle,

            My father’s brother; but no more like my father

            Than I to Hercules.  Within a month,

            Ere yet the salt of most unrighteous tears

Had left the flushing of her galled eyes,

            She married.  O, most wicked speed, to post

            With such dexterity to incestuous sheets!

It is not, nor it cannot come to good.

            But break my heart, for I must hold my tongue. (Lines 129 – 159)

In the first place, this speech makes it quite easy to see that the most intimate interaction of abstract thought and imagination is necessary to the form that is taken by reason when it truly represents the substantial form of a human being. Because it is so rich in this interaction and its elements flow so freely into each other in its sense, Hamlet’s soliloquy is far from being an expression of remote and specialized reasoning and is illuminatingly close to a rational argument that might arise in ordinary experience. This, of course, is generated by Shakespeare’s mastery of dramatic form and his powerful conception of the character’s psychology and circumstances.

   Abstract thought gives the speech its structure in the form of three main themes that depend in quite obvious ways upon ideas, judgements and logical reasoning. The first of these themes (from lines 129 – 37) is an outpouring of feeling interwoven with a judgement on the world in which Hamlet finds himself; the second is a disillusioned reflection on his experience of his parents in the past and the harmony that he sensed to exist between them (lines 137 – 146); the third uses this past experience to deliver a damning judgement on his mother. Each of the themes is coherently reasoned but the speech is not a series of strictly presented arguments, it is closer to a ruminative reflection that is guided by reason, and it has overlapping parts that allow the themes to flow one into another (lines 147 – 9 return to the subject matter of the second theme as an impulse for developing the third, the logic of which is to provide a pitiless resolution to the second theme).

   We can already see in this scheme that the abstract reasoning that lies in an interweaving of ideas, judgements and logical thinking depends for its substance upon Hamlet’s past experience, the shocks that have been suffered by him in recent events, his distant memories and hitherto settled conception of his parents’ marriage, and the depth of his attachment to these memories and their significance to him. Furthermore, it is obvious that in the absence of this experiential substance, or something like it, there would be nothing with which his abstract thought could engage, and therefore nothing for it to reveal. What is more elusive, something of the intricacy of the relation between abstract thought and imagination is evident in the transition from the imagery of corrupted nature in lines 7/9 to the sense of outrage behind his mother’s marriage to Claudius (lines 9/10). In these lines the uncontrolled spreading of what is rank and gross in nature is logically connected with the spreading sense of disorder in Hamlet’s self-awareness in relation to his altered circumstances. Moreover, the disorder extends beyond the marriage itself, for earlier in the scene (Act 1, scene ii), we have been made aware that through Claudius’ authority, and with Gertrude’s approval, Hamlet is deprived of his freedom to travel outside of Denmark, and is now a pariah to the court. We can see in this example that just as abstract thought acts in terms of imagination and related sensory experience (such as imagery from nature), so sensuous figurative language makes its own contribution to the logic and abstract formulations of the verse.

   Hamlet’s creation from memory of an intense fantasy of his father’s tender care for his mother provides another rich confluence of judgement and imagination. Here the logic involves a flight of imagination that conveys a sense of elation, one that has, no doubt, some basis in Hamlet’s experience, but is also heightened for the expression of disillusionment. This, too, involves abstract thought in sensuous experience, the abstract thought of an explicitly ironic contrast; memory and imagination give an airy life to one side of the contrast (‘beteem the winds of heaven’) while the imagery acts as a vehicle for the abstract thought.

   The give-and-take relations between abstract thought and imagination (sustained by memory, sensory experience and figurative language) are taken to greater psychological depths in the third and concluding theme. In this part of the soliloquy Hamlet reveals most of himself, both in what he says and in what he doesn’t say, and this gives a further complexity to his thought in the two elements with which we are concerned. What is demonstrated in relation to dramatic form, in connection with the interdependence between abstract thought and imagination obviously applies with equal force to our ordinary understanding of ourselves and other people, and therefore to our understanding of human life in general. The venom in Hamlet’s condemnation of his mother is sharpened by its having been held back, and this is closely related to his holding back the true reason for his disquiet. 

   In connection with abstract thought, he is almost fastidiously rational, and obliquely draws attention to this (‘a beast that wants discourse of reason / Would have mourned longer’), and it is impossible to argue with the broad outline of his attack – Gertrude’s offence is undeniable in any reasonable terms. In parallel with this is a more rhetorical repetition of the same ideas in different words, which suggest a habitual preoccupation with his mother’s insincere display of grief and the incestuous nature of her marriage to Claudius. The effect of fastidious reasoning overlapping with rhetorical repetition contributes in particular to an expression of conviction in which abstract thought is an imaginative force and imagination asserts itself as reason. As if to validate the process, Hamlet includes a curiously personal allusion at the point at which the nature of the marriage is first mentioned. The lines, ‘Married to my uncle, / My father’s brother; But no more like my father / Than I to Hercules’, insinuate the nature of the marriage in the bald statement of sibling relationship, and in doing so they also insinuate a sexual relationship between Claudius and Gertrude. Both ideas come together with some force a few lines later (O, most wicked speed, to post / With such dexterity to incestuous sheets!). However, it is also relevant that a moment of moral fastidiousness steals into his reasoning, as the comparison of himself to Hercules betrays a sense of the unheroic appraisal of his mother. What is to become an obsession, that her attraction to Claudius is sexual in nature, has no basis in reason or observation – it is certainly not confirmed by their behaviour towards each other in the action of the play. These two things together, obsession with the idea of a sexual violation that Hamlet has invented and his accidental acknowledgement of a hidden motive for it, indicate the true reason that is held back; pride stops him from admitting that the real source of his anguish is that, in entering this marriage, his mother abandons him.

   This soliloquy does not demonstrate the use of abstract thought as the purely logical enquiry that we might expect to find, for example, in mathematics or physics. However, the mutual involvement of abstract thought with imagination that we find in ordinary experience provides us with a true insight into the nature of such thought and its relation to the form that is taken by human life. Shakespeare’s use of dramatic form shows us such life in action and thereby reveals the subtle interdependence of our faculties in the exercise of reason. This implies that dramatic form itself is a kind of abstract thought. In the foregoing analysis, we have seen examples of how judgement, ideas and coherent portrayal are extended by figurative language, the evocation and embellishment of memories and the representation of unconscious motives. Reason is animated by its immersion in the experience of a character, and because, in this case, insight is unerringly true to our understanding of ourselves and others, there is a convincing integration of reason with imagination. Hence the soliloquy shows us how the abstract thought that succeeds in representing the substantial form of human life is one that includes in its characterization the very interdependence of reason and imagination that makes this representation possible.

   This refers to a relation that is necessary between the substantial form of human life and the form of abstract thought that truly represents such life. Thus, it enables us to see that human life cannot be truly represented by an immaterial abstract thought that is autonomous and sovereign over all other human attributes. Moreover, we cannot defend the view that a person is a composite or compound of mind and body, in the sense that a chisel is a composite of metal blade and wooden handle or that wine is a compound of fermented grape and water. The abstract thought of ideas and concepts, calculations and judgements, and logical reasoning has no independent reality as the expression of a substantial form of life of any kind. As we have already seen, it is an extension of the sensory perception and related world of feeling that is identified with the realization of physical objects – including oneself.

   This is not an eccentric suggestion; when I see a cup, I have an immediate experience of a vessel for drinking tea or coffee, and this is an abstract object – the cup is both physically concrete and abstract, and the same is true of any other physical object. For another animal, such as a lizard, the object will not be what it is for me but it, too, will be both concrete and abstract; we must assume that the physical object in general will be abstract to any sentient being and that its constitution will be determined by a specific act of sensory perception. Thus, it becomes very likely that in different sentient beings there are different possibilities for the development and elaboration of the abstract element that is fundamental to the realization of physical objects in sensory perception. And in human experience we can see that this kind of development is given scope and refinement by language. Therefore, not only can a sentient being that uses language find new resources for the development and refinement of abstract thought itself, but, as we have seen in Shakespeare’s mastery of dramatic form, it can develop and refine the relations between abstract thought and imagination that make it possible to portray itself in action, and thereby reveal the substantial form of its own life.

   This argument is a challenge to the Aristotelean idea that the substantial form of a person is exclusively that of a rational being. However, its underlying purpose has been to replace this idea with something that is more encompassing. The idea of a person as essentially a creature that reasons is constructed on the basis that abstract thought is immaterial and therefore both irreducible to other human attributes and sovereign over them. We have seen that neither of these assumptions can survive the close examination of relations between abstract thought and imagination in ordinary experience, and this is the test of what must be true for the substantial form of a person. That reason plays a part in this form is undeniable, but what this argument shows is that it plays a part in reflectiveness. In other words, reason is a natural resource of a sentient being for which life is valued in itself. Reason makes it possible to enhance and transform a life that is so valued, but as we have also seen, it has purpose only in relation to the experiential substance of such a life.

Phenomena as Substance and Sensory Perception as its Realization: Affinity of Sensory Perception to Reasoning; Intersubjectivity and the Essence of Things

In this argument, the inner life of sentient being is seen as having its origins largely in the relation of the physical object to the act of sensory perception that realizes it. In this respect, psychological depth, or ‘soul’, emerges from the cumulative experiences – along with reflection and the events that make up our lives – of realizing what is physical and an intersubjective human world. 

   In this light, we can consider an alternative to the psychological mechanism of association: the experience of travelling on a bus might, without any identifiable association, bring vividly to mind the imagery connected with train journeys of thirty years earlier. Our natural inclination is to look for something that makes us associate the present experience with what happened to us in the past. However, it is possible for the relation to be the other way around. A sense of the earlier experiences may be there because they have contributed substantially to the present experience of travelling on the bus, and helped to give the objects of this experience their character (this would explain the elusive nature of the connection and why there is no clear association). In the past experience that gives the physical object its character the whole of my experience of life may be immanent, but certain earlier experiences will be more sensitive, and therefore more actively aroused, than others. This suggests something like a merging of numerous past experiences, and perhaps of different kinds, in the realization of a physical object. The object is not put together physically but realized abstractly in terms of its character. Past experience is not just a stock of images and objects, it is equally a history of experiences which include acts of sensory perception (themselves constituted by past experience), memories and imaginings. What gives character to the present object is extremely elusive and in more ways than one.

   To illustrate this example, let us say that the train journeys of the past included occasionally taking the train to see football matches at a certain ground, and that the excitement and mild elation of this prospect flows into the present experience of travelling on the bus. The elusiveness of this kind of evocation of the past is such that, though it might create a transient awareness of the train journeys, the feeling of elation might be quite detached from its earlier cause – there might be no recollection of football matches at all. Then there would only be the sharp and brief memory of much earlier experiences of travelling shot through by a mysterious feeling of joy. This fragmentary assimilation of past experience into the realization of the physical object can be assumed to be governed by some sense of the values attaching to the object, and to take numerous different forms. At the same time, however, our experience is generally consistent, and so much of the influence of past experience must be logically related and predictably cumulative; an interior that is known to us over many years is given its character in a very similar manner day after day, and, from this point of view, its changes are imperceptible. Very rarely we might remember how differently a place seemed when it was first seen, many years earlier.

   The whole of my past experience is latent in what is experienced by me now. What might be available to memory is always latent within experience, and, in this respect it is continuously alive in the moment as it is lived. The act of sensory perception highlights past experience in specific ways so as to define the character of the object. Conversely, if my past experience were not in certain ways alive in what I experience now, then the things that I perceive now would have no character and I would not experience anything. It is not surprising that, sometimes, present experiences evoke occasions or patterns of experience from the past because these occasions or patterns constitute the present experience in the first place.

   In this account of how the physical object acquires its character there is some affinity between reflective experience and rationality. I have already made the point that the realization of the object is abstractive in nature and that in seeing a cup as a vessel for drinking tea or coffee it is perceived as the representation of an idea. We might take this connection of sensory perception with abstract thought and reason even further. Hence the subtle interweaving of past experiences in the realization of the object implies more than simply the sense that is given to a discrete object, since it can easily be extended to incorporate the sense of an intelligible world and self-awareness that are also essential to our perception of any object. If there are many complex and interconnected ways in which things must be related in order for an object to be realized, then the systematic orders of phenomena to which a cup necessarily belongs must also be at least implicit in our vision of it. This greatly increases the range of abstract thought that is implicitly active within the act of sensory perception as a realization of the physical object.

   The bare sensory experience of a cup, for example, could not occur without some apprehension of how cups exist in a physical setting of dining equipment, tables, rooms and dwellings and so on. They must also exist within orders of social life that belong to the history of a particular form of life. In this connection, the abstract thought that applies to seeing a cup as a vessel for drinking tea or coffee, can be applied to the general intelligibility of the physical object as something that is realized in sensory perception, and this implies a rational experience before we exercise any deliberate calculation or judgement, or engage in logical reasoning. The physical object is not only abstractive and aesthetical, it has a context, or a number of contexts, that are also abstract in nature. Thus, it is misleading to assume that sensory perception is merely a primitive and rudimentary form of apprehension that provides coarse data for a more sophisticated abstract thought of ideas, judgements and logical reasoning.

   So, while the sensory perception of a cup is not the same as a judgement or an example of logical reasoning, there is, in this perception, a kind of abstract thought that is both extensive in relation to inner experience and cognitively significant. To suggest an example that makes the connection between the act of sensory perception and the abstract reflection of judgements, calculations and logical reasoning, we might consider the response of a European to the oriental cups of China and Japan, which are without handles. In trying to guess why oriental cups do not have handles, a European might see in a particular example that the cup without handles possesses a simple unity that greatly enhances its shape and aesthetic effect. In following this line of explanation, sensory perception would be enough to provide a secure basis for the judgement that Chinese or Japanese civilization is one in which aesthetic sensitivity to ordinary objects like cups plays an important part. In short, the acute sensory perception of an artefact is a legitimate grounding for logical reasoning about the character of a civilization. Such reasoning does not come from a separate immaterial realm but builds naturally on the mutual involvement of materiality and self-awareness that belongs to sensory perception of the physical object.

   The psychological proximity of what is abstract in sensory perception to the abstract reflection that we exercise in logical reasoning can be seen very widely in the experience of a reflective being, and it is especially conspicuous in the creation and enjoyment of art. Wherever the meaning and significance of phenomena are affected by the sensory character of the physical object, or in language alluding to this, there is a sensory grounding for the logical reasoning that enables us to understand the phenomenon. So, the illuminating interpretation of a poem, play, novel, painting, sculpture or musical composition depends upon our response to the artist’s employment of a sensuous medium – for example, we must be able to see how a poet’s use of sound and figurative language affects the meaning of the poem. Without this kind of sensitivity, it is impossible to see into the logic of the work of art as a portrayal of reflective life in action. Something similar is true of our interpretation of a person’s appearance and behaviour, as, for example, when we recognize something in his or her change of mood or realize that he intends to deceive us. 

   We have seen that sensory perception is not a substance (material or immaterial) but rather the realization of a physical object, and that the character of the object is determined by the past history of the perceiver. Its identity is acquired from the present and past experience of a sentient being. Therefore, the sensory realization of the object characteristically presents an abstract thought or idea to reflection and logical reasoning, should it be desired. The smooth continuity and mutual exchange of these two modes of perception, one abstractly sensory and the other reflectively abstract, is necessary to insight into any psychological action that we might consider to be significant. It is equally relevant, moreover, when the thought or idea is presented in an ordinary and uncontentious way – for example, when we immediately accept the truth of what is said to us we automatically assume (perceive) the speaker to be sincere. 

   The cup has an identity because its constitution is determined intersubjectively by the past history of a sentient being acting psychologically upon the incipient object. What gives a cup its essence as a vessel for drinking tea or coffee lies in its being used in this way by many sentient beings; however, it does not lie in its being used in this way by all sentient beings, or even by all people. The cup acquires its essence not from being universally a vessel for drinking tea or coffee, but from its being defined intersubjectively in this way by what the subject knows it to be for others. Accordingly, the past experience in response to which I realize the cup as a vessel for drinking tea or coffee is more than a history of discrete perceptions of similar phenomena; in each case the perception must incorporate some sense of the world to which cups belong, an intelligible context or set of contexts. This will be a social world of experience that is indirectly intersubjective in being known as a world in which many other people see the cup as I see it. What is true of a cup is true of any physical object from a speck of dust to the cosmos; the object is not universally one thing or another, its essence is defined intersubjectively by how the object is generally seen in the life in which I participate.

   According to this definition, the essence of an object lies more in how it is valued and fits into an intelligible world than in what is strictly true of it physically. In medieval Europe, the sun was thought to move around the earth and we now know that this does not express the essence of anything to do with cosmology. Obviously, there is a contradiction: if the intrinsic nature of the object, or its essence, lies in the intersubjective perception of how it is generally understood then how is this compatible with a conception of its essence that is simply untrue to its physical relations? 

   This contradiction is interesting because it cannot be resolved by saying, ‘Correct the misapprehension by making the earth move around the sun, and decide that this is the essence that will be defined intersubjectively when it is known to many people’. The intersubjectivity of the essence of things is an expression of an intelligible context or set of contexts, and this cannot be corrected simply by deciding that the earth must be seen to move around the sun, even if that is what actually happens. For example, in one context the motion of the sun around the earth is essential to the perpetuation and growth of living things; plants and crops thrive in accordance with the rhythms of warmth and light that are created by the rising and setting of the sun and day and night. Similarly, in animals the patterns of light and darkness accord with wakefulness and sleep promoted by the motion of the sun in relation to the earth. To a medieval man the motion of the earth around the sun would seem to destroy the rhythms and patterns upon which life obviously depends.

   With respect to this context, we know that the sun moves around the earth, not in the sense that the former encircles the latter but because the earth rotates as it encircles the sun, and so we can avoid the apparent contradiction with what we experience. In another context, however, there is no such easy resolution and intelligibility is subjected to a crisis by the cosmological revolution. When motion of the sun and stars around the earth is seen as a confirmation of a transcendental concern with human life that expresses its centrality and ultimate importance, the displacement of relations between the sun and earth has a different kind of significance. In this context, there is no room for an adjustment to the physical details and we are left with a stark contradiction between an intersubjective essence of the world as geocentric and intelligible, and the physical facts that violate this belief and the intelligibility with which it is connected. The unappealing alternatives to this contradiction can only be to abandon belief in a transcendental concern with human life, or to find another way in which this belief is affirmed by the essence of the cosmos.

   This example demonstrates an instability that lies at the heart of our understanding of the physical object, and of our conception of its essence. It arises out of the determination of the object by the past experience of a sentient being, along with the intersubjectivity that this entails, and relations between the object and its belonging to an intelligible world. Taken together these factors imply that on one hand the object is created by an act of sensory perception that is given its substance by intersubjective involvement, and on the other hand the essence of the object is defined by the intersubjective perception of how it is seen by others. This means that there is a circular process in which the realization of the physical object fundamentally determines its essence; the object does not possess a separate essence that is independent from how it is perceived. Thus, while every significant change in our perception of an object alters its essence, our conception of the physical facts can be changed without necessarily altering the intelligibility that goes with them. As the example shows, this can lead to contradiction in the ways in which we grasp the essence of a physical object. 

   This account shows that substance is generated in the physical object by an act of sensory perception that is informed by a sentient being’s experience as it is intersubjectively determined by participation in a common life. Substance lies in the object and not in the subliminal psychological action that is its realization. In the perception of a cup, for example, the substance can be defined in most cases as its being a vessel for drinking tea or coffee, and its realization by an act of sensory perception is a psychological action and not, in this connection, itself the substance of an object. However, this action is a characteristic form of experience in another physical object, a sentient being, and a sentient being is perceived by itself and other sentient beings to possess its own substance. With respect to a sentient being, the psychological action of perceiving an object does belong to the substance of an object, as the psychology and perceptions of a sentient being are essential to its character. Hence, in an act of sensory perception there is a physical object (or a number of objects) and one realm of substance that lies in the object as it is realized by the perceiver. In the realization of a cup there is the cup’s realm and in the realization of a person there is the person’s realm, and this latter realm includes psychology and perceptual experience. For both, realization of the object is not itself a substance, any more than realization (formulation) of a plan is itself a plan, or realization (formation) of an intention is itself an intention. In so far as perception can change, the essence of the object is unstable, and change can be radical and dramatic or slight to the point of being barely perceptible. Whatever the degree of particular changes there is an underlying flux in which things are re-formed, not only physically but by the constant renewal of their realization in the experience of sentient beings.

   To dispel any suspicion of ambiguity in this argument, we might examine examples that show how substance belongs to the object and not to its realization. First, with respect to sensory perception of oneself, an artist considers his ability to execute a task that is beyond the powers of other painters. When he thinks about this task in relation to his abilities, he calmly supposes that there is no reason to doubt that he will succeed. Realization of the physical object (himself) lies in the recognition of his own tranquillity in the face of a challenge, and is a physical response to his own psychology and perceptual experience. This is the substance of his sensory perception, and substance does not lie in the act of sensory perception that realizes it. With respect to the sensory perception of another person, x might see y as a devious individual of bad will, and have a settled view of him as untrustworthy. It might be claimed that, in this case, the sensory perception itself has substance as an expression of x’s character, and could be interpreted as his wildly personal distortion of y’s character. However, this judgement does not refer directly to x’s perception of y, but rather to a subsidiary perception, of x, which might or might not be sensory. This, of course, could be made by x himself; the point is that it would be the expression of another perception or judgement, and not of the original substance. There is a distinction to be made between the realization of y and the psychology and history of perceptual experience that lie behind it and form x’s character. 

   This conception of knowledge does not represent a stable underlying moral state of affairs, but suggests a tussle of perceptions and judgements that possess varying degrees of accuracy, detachment and insight in individuals of contrasting interests and points of view. Because the object and its realization are not two different substances but a relationship that is necessary to one substance the situation is monistic. The physical object is realized by means of the sensory perception that gives it character, and without this constructive psychological action there is no phenomenon. Hence, as we have seen, the object is given its essence by an act of sensory perception, making perception a primary source of abstract ideas. This implies that abstract thought and reasoning are not separate and immaterial but continuous with sensory perception. There is need, therefore, for neither a neutral substance that is physical when seen in one way and sensory when seen in another, nor the hylemorphic dualism that depends upon an immaterial substance. 

Related Texts

Aristotle, De Anima (11. 1, 412b4, 111. 4, 429a25). Read online ebooks.adelaide.edu.au/a/aristotle/a8so

Aristotle, De Generatione Animalium (11, 736b28). Read online archive.org/details/generationofanim00arisuoft 

Nelson B. R. Forms of Enlightenment in Art. Cambridge: Open Angle Books, 2010

Nelson B. R. Sensory Knowledge and Art. Cambridge: Open Angle Books. 2018

Oderberg, David. ‘Hylemorphic Dualism’ in E.F. Paul, F.D. Miller and J. Paul (eds) Personal Identity(Cambridge University Press, 2005) 70-99.

Russell Bertrand, The Analysis of Matter. London: Kegan Paul. 1927