The present article must be limited to a discussion of the metaphysical theories of mind. Owing to the peculiar position which these problems occupy in philosophy, as well as in the study of ethical and religious problems, it is advisable, first of all, to make explicit some of the epistemological problems which especially confront the student of the nature of mind; and in order to do this, we must, in view of numerous traditional complications which beset the theory of the knowledge of mind, open our discussion with some general statements concerning the nature of problems of knowledge.
The history of epistemology has been dominated by a well-known contrast between two kinds of knowledge, namely, perceptual knowledge and conceptual knowledge. This dual contrast seems insufficient to supply us with a basis for a really adequate classification of the fundamental types of knowledge. It is proposed in the present article to base the whole discussion upon a threefold classification of knowledge. Having begun with this threefold classification and briefly illustrated it, we shall go on to apply it to the special problems which we have to face in dealing with mind. We shall then consider -in some detail what kinds of mental facts correspond to the three different kinds of knowledge thus defined. In conclusion, we shall deal with some problems of the philosophy of mind in the light of the previous discussion.
I. Perception and conception as fundamental cognitive processes.-A careful study of the processes of knowledge, whether these occur in the work of science or in the efforts of common sense to obtain knowledge, shows us three, and only three, fundamental processes which are present in every developed cognitive activity and interwoven in more or less complicated fashion. Of these two have been recognized throughout the history of science and philosophy, and their familiar contrast has dominated epistemology. The third, although familiar and often more or less explicitly mentioned, was first distinguished with sharpness, for epistemological purposes, by the American logician, Charles Peirce. We shall speak first of the two well-known types of cognitive process, perception and conception.
The name 'perception' is used in psychology with special reference to the perceptions of the various senses. We are here interested only in the most general characteristics of perception. William James has used, for what is here called perception, the term 'knowledge of acquaintance.' He distinguishes 'knowledge of acquaintance' from 'knowledge about.' In the simplest possible case one who listens to music has 'knowledge of acquaintance' with the music; the musician who listens in the light of his professional knowledge has not only 'knowledge of acquaintance,' but also 'knowledge about'; he recognizes what changes of key take place and what rules of harmony are illustrated. A deaf man who has learned about the nature of music through other people, in so far as they can tell him about it, but who has never heard music, has no 'knowledge of acquaintance,' but is limited to 'knowledge about.' 'Knowledge of acquaintance' is also sometimes called 'immediate knowledge.' In the actual cognitive process of the individual human being it never occurs quite alone, since, when we know something perceptually or by acquaintance, we-also always have more or less 'mediate' knowledge, i.e., one who listens to music, but who also considers the person of
(148) the artist, the relation of the music to the programme, the name of the composer, or the place of this experience in his own life, has in his knowledge that which is more than the immediate hearing of the music.
'Knowledge about' includes, on occasion, mental processes which may vary very widely and which may be mingled with 'knowledge of acquaintance' in ways which are far too complex to analyze here. But 'knowledge about' is especially opposed to 'knowledge of acquaintance' in one class of cases which need to be emphasized through the use of a special name. We may name that class by calling the kind of knowledge involved in it by the name already used, 'conceptual knowledge.' Conceptual knowledge is knowledge of universals, of relations, or of other such 'abstract' objects. The Socratic-Platonic theory of knowledge called attention from its very beginning to universals and relations, and consequently made this type of knowledge specially prominent.
No doubt, even if one is disposed to cling to this merely dual classification of knowledge, one may well question whether all knowledge which is not merely 'knowledge of acquaintance' is of the grade of conceptual knowledge. For there is much 'knowledge about' concerning which we should all hesitate to say that it is knowledge of universals. Socrates himself, in his effort to define the knowledge of universals, met at the start with the fact that much of our knowledge of universals is confused and inarticulate. But if, for the moment, we neglect the intermediate cognitive states in which we more or less mingle 'knowledge of acquaintance' and conceptual knowledge, or possess conceptual knowledge in imperfect degrees of development, we may readily admit that this traditional dual classification of cognitive states is sufficient to call attention to a distinction which is of the utmost importance, both for empirical science and for metaphysics.
While the distinction between perceptual and conceptual knowledge is of great importance in determining the distinction between the deductive and the
(149) inductive methods in the sciences, the classification of these two modes of cognition does not of itself suffice to determine what constitutes the difference between inductive and deductive science. When we have clear and accurate conceptual knowledge, we are in general prepared to undertake scientific processes that in the case of further development will involve deductive methods. Thus, in particular, a conceptual knowledge of universals leads, in the mathematical sciences, to the assertion of propositions. Some of these propositions may appear at the outset of a science as axioms. Whether accepted as necessarily true or used merely as hypotheses, these propositions, either alone or in combination, may, and in the mathematical sciences do, form the starting-point for a system of rational deductions. The type of knowledge involved in this deductive process will be, in the main, the conceptual type. In what sense and to what degree a 'knowledge of acquaintance' enters into a process of mathematical reasoning we have not here to consider. All will admit that the sort of knowledge which dominates such a deductive process is 'abstract,' is concerned in reaching results which are true about the propositions that themselves form the premisses of the deduction. And so our knowledge concerning numbers, the operations of a mathematical science, and similar cases form exceptionally good instances of what characterizes conceptual knowledge in its exact and developed form.
In the inductive use of scientific methods we find a more complicated union of the perceptual and the conceptual types of knowledge. When a hypothesis, such as Newton's formula for gravitation, or Galileo's hypothesis concerning the laws of falling bodies, is stated, the type of knowledge involved in formulating and in understanding the hypothesis is prevailingly conceptual. When the hypothesis is tested by comparing the predictions based upon it, with experience, the test involves appealing at some point to perceptual knowledge, or 'knowledge of acquaintance.' The processes of experiment used in an inductive science
(150) might seem to be typical cases of processes involving perceptual knowledge. And experiments unquestionably do involve such knowledge. But an experiment reveals a truth, because it brings concepts and percepts into some sort of active synthesis. Upon such active synthesis depends the process of validation which is used as the basis for the definition of truth used by recent pragmatists.
In so far as we insist upon this dual classification of fundamental processes of cognition, the questions which most come to our notice, regarding both knowledge and its objects, concern (1) the relative value of these two cognitive processes, and (2) the degree to which, in our actual cognitive processes, or in ideal cognitive processes (such as we may ascribe to beings of some higher order than ours), the two can ever be separated. These two questions have proved especially momentous for the theory both of knowledge and of reality.
(1) Regarding the relative value of the two fundamental types of cognition, Plato, as is well known, held that conceptual knowledge is the ideal type, the right result an expression of reason. Conceptual knowledge gives truth; perceptual knowledge gives illusion or appearance--such is, on the whole, the Platonic doctrine. In recent discussion the pragmatists--and still more emphatically Bergson--have insisted upon the relative superiority of the perceptual type of knowledge. The familiar expression of this view is the thesis of recent pragmatism that conceptual knowledge has only a sort of 'credit value'; perceptual knowledge furnishes the 'cash of experience'; conceptions are 'bank notes'; perceptions, and perceptions only, are 'cash'. The statement of Bergson goes further, and declares that, if we had unlimited perceptual knowledge, i.e. 'knowledge of acquaintance' whose limits and imperfections we had no occasion to feel, because it had no limits and no imperfections, then conceptions could have no possible interest for us as cognitive beings. In other words, we use concepts, i.e., we seek for a
(151) knowledge of universals, only when our perceptions in some way fail us. Conceptual knowledge is in its very essence a substitute for failing perceptual knowledge. The opposition between Plato and Bergson regarding this estimate of the relative significance and truthfulness of the two kinds of cognitive processes is thus characteristic of the contrast which is here in question. Of course all the philosophers admit that, in practice, our knowledge makes use of, and from moment to moment consists in, a union which involves both conceptual and perceptual processes.
(2) On the question whether the two foregoing types of knowledge, however closely linked in our normal human experience, can, at least in ideal, be separated--i.e., whether a knowledge by 'pure reason' is possible on the one hand, or a knowledge of 'pure experience' is ever attainable on the other hand--the historical differences of opinion are closely related to well-known metaphysical controversies. For Plato, as (in another age, and in a largely different metaphysical context) for Spinoza, it is at least in ideal possible for philosophy, or for the individual philosopher, to attain a purely intellectual insight into the realm of 'ideas' or into the nature of the 'substance.' For various forms of mysticism, as well as for theories such as the one set forth in the Kritik der reinen Erfahrung (Leipzig, 1888-90) of R. H. L. Avenarius, a mental transformation may be brought about through a process which involves either a practical or a scientific correction and gradual suppression of erroneous intellectual illusion; and, at the limit of this process, reality becomes immediately and perceptually known, without confusion through abstractions.
The 'radical empiricism' of James's later essays makes use of a theory of knowledge which attempts, as far as possible, to report, apart from conceptual constructions, the data of pure experience.
2. Interpretation through comparison of ideas as a third fundamental cognitive process.--It is an extraordinary example of a failure to reflect in a thoroughgoing
(152) way upon the process of knowledge that until recently the third type of cognitive process to which we must next refer has been neglected, although every one is constantly engaged in using and in exemplifying it.
When a man understands a spoken or written word or sentence, what he perceives is some sign, or expression of an idea or meaning, which in general belong to the mind of some fellow-man. When this sign or expression is understood by the one who hears or who reads, what is made present to the consciousness of the render or hearer may be any combination of perceptual or conceptual knowledge that chances to be in question. But, if any one cries 'Fire!', the sort of knowledge which takes place in my mind when I hear and understand this cry essentially depends upon this fact; I regard my fellow's cry as a sign or expression of the fact either that he himself sees a fire or that he believes that there is a fire, or that, at the very least, he intends me to understand him as asserting that there is a fire, or as taking an interest of his own in what he calls a fire. Thus, while I cannot understand my fellow's cry unless I hear it, unless I have at least some perceptual knowledge, and while I equally shall not have a 'knowledge about' the nature of fire, and so a 'knowledge about' the object to which the cry refers, unless I am possessed of something which tends to be conceptual knowledge of his object, my knowledge of my fellow's meaning, my 'grasping of his idea,' consists neither in the percept of the sign nor in a concept of its object which the sign arouses, but in my interpretation of the sign as an indication of an idea which is distinct from any idea of mine, and which I refer to a mind not my own, or in some wise distinct from mine.
It is to be noted that, however we reach the belief in the existence of minds distinct from our own, we do not regard these minds, at least in ordinary conditions, as objects of our own perceptual knowledge. For the very motives, whatever they are, which lead me to regard my perceptions as my own even thereby lead me to regard my fellows' perceptions as never present
(153) within my own field of awareness. My knowledge of my own physical pains, of the colours that I see, or of the sounds that I hear is knowledge that may be called, in general terms, perceptual. That is, these are objects with which I am, or upon occasion could be, acquainted. But with my fellow's pains I am not acquainted. To say this is merely to say that, whatever I mean by 'myself' and by 'the Alter,' the very distinction between the two is so bound up with the type of cognition that is in question that whatever I am acquainted with through my own perception is ipso facto my own object of acquaintance. Thus, then, in general, perceptual knowledge has not as its object what is at the same time regarded as the state of another mind than my own.
But, if the mind of my fellow, in particular his ideas, his feelings, his intentions, are never objects of perceptual knowledge for me, so that I am not directly acquainted with any of these states, must we regard our knowledge of the mind, of the ideas, of the intents, purposes, feelings, interests of our fellow-man as a conceptual knowledge? Is our fellow-man's mind the object of a concept of our own? Is the fellow-man a universal, or a relation, or a Platonic idea? Wherein does he differ from a mathematical entity or a law of nature? Unquestionably we regard him as possessing conceptual knowledge of his own, and also as engaged in processes of knowledge which may be conceptual, or which may involve any union of percept and concept. But the fact remains that neither by our own perceptions can we become acquainted with his states of mind, nor yet by our own conceptions can we become able to know the objects which constitute his mental process. Ii: fact, we come to know that there are in the world minds not our own by interpreting the signs that these minds give us of their presence. This interpretation is a third type of knowledge with is closely interwoven with perceptual and conceptual knowledge, very much as they in turn are bound up with it, but which is not reducible to any complex or combination consisting of elements which are merely perceptual or merely conceptual.
Every case of social intercourse between man and man, or (what is still more important) every process of inner self-comprehension carried on when a man endeavours to 'make up his own mind' or 'to understand what he is about', involves this third type of cognition, which cannot be reduced to perception or to conception. It is to this third cognitive process that, following the terminology which Peirce proposed, we here apply the name 'interpretation.'
In order to distinguish more clearly the three types of cognition, we may say that the natural object of perception is some inner or outer datum of sense or feeling, such as a musical tone, a colour, an emotional state, or the continual flow of the inner life upon which Bergson so much insists. For these are typical objects of perceptual knowledge, _i.e. of 'knowledge of acquaintance.' The typical objects of conceptual knowledge are such objects as numbers, and relations such as identity and difference, equality, and so on. But typical objects of interpretation are signs which express the meaning of some mind. These signs may be expressions of the meaning of the very mind which also interprets them. This is actually the case whenever in memory we review our own past, when we reflect upon our own meaning, when we form a plan, or when we ask ourselves what we mean or engage in any of the inner conversation which forms the commonest expression of the activity whereby an individual man attains some sort of explicit knowledge of himself.
The form of cognitive process involved in the social relations between man and man is essentially the same a as that involved in the cognitive process by which a man makes clear to himself his own intent and meaning. For, despite well-known assertions to the contrary on the part of Bergson, nobody has any adequate intuitive 'knowledge of acquaintance' with himself. If such perceptual or intuitive knowledge of the self by the self were possible, we should not be obliged to acknowledge that the world of human beings is dominated by such colossal and often disastrous ignorance of every man
(155) regarding himself, his true interests, his real happiness, his moral and personal value, his intents, and his powers, as we actually fine characterizing our human world. In brief, man's knowledge, both of himself and of his neighbour, is a knowledge which involves an interpretation of signs. This thesis, very ably maintained by Peirce in some of his early essays, involves consequences which are at once familiar and momentous for the theory of knowledge.
That the type of knowledge involved whenever signs are interpreted is a fundamental type of knowledge which cannot be represented either to perception or to conception can be exemplified in most manifold ways, and will appear somewhat more clearly through the illustrations given below. It may be useful to point out here that, while all our interpretations, like all our perceptual and conceptual knowledge, are subject to the most manifold illusions in detail, it still remains the case that, whenever one is led to attempt, propose, or believe an interpretation of a sign, he has actually become aware, at the moment of his interpretation, that there is present in his world some meaning, some significant idea, plan, purpose, undertaking, or intent, which, at the moment when he discovers its presence, is from his point of view not identical with whatever idea or meaning is then his own.
If somebody speaking to me uses words which I had not intended to use, I may misunderstand the words, or I may not understand them at all. But, in so far as I take these words to be the expression of a meaning, this meaning is one that just then I cannot find to be my own--i.e., these words do not express my ideas, in so far as these ideas are by me interpreted as my own. The cognitive process here in question divides, or at least distinguishes, that part of the objects, ideas, or meanings in question into two distinct regions, provinces, or modes of mental activity. One of these regions is interpreted at the moment as .'my own present idea,' 'my own purpose,' 'my own meaning'; the other is interpreted as 'some meaning not just now
(156) my own,' or as 'some idea or meaning that was once my own'--_i.e., as 'my own past idea,' or as 'my neighbour's meaning,' or perhaps as 'a meaning that belongs to my social order,' or 'to the world,' or, if I am religiously minded, 'to God.' In each case the interpretation that is asserted may prove to be a wrong one. Interpretation is fallible. So, too, is conception, when viewed as a cognitive process, and so is perception, whose character as 'acquaintance with' is no guarantee of its accuracy, whether mystical apprehension or ordinary observation is in question. The fact for our present purpose is not that our human knowledge is at any point infallible, but that there is the mode or type of cognition here defined as interpretation. Interpretation is the knowledge of the meaning of a sign. Such a knowledge is not a merely immediate apprehension, nor yet a merely conceptual process; it is the essentially social process whereby the knower at once distinguishes himself, with his own meanings, ideas, and expressions, from some other self, and at the same time knows that these selves have their contrasted meanings, while one of them at the moment is expressing its meaning to the other. Knowledge by interpretation is, therefore, in its essence neither mere 'acquaintance' nor yet 'knowledge about.'
There is another way of expressing the distinction of these three kinds of knowledge which proves useful for many purposes. Knowledge of the first kind, 'knowledge of acquaintance,' may for certain purposes be characterized as 'appreciation.' Conceptual knowledge, owing to the means often employed in making a concept explicit, may be for many purposes called 'description.' In each case, as will be noted, the main character of the type of knowledge in question can be designated by a single term, namely, appreciation or description, just as in the foregoing these two types of knowledge have been designated each by a single term, acquaintance in one case and conception in the other.
In designating the instances of interpretation it is well to note that every interpretation has three aspects.
( 157) For the one who interprets it is an expression of his own meaning. With reference to the object, i.e. to the sign, or to the mind whose sign this is, the interpretation is the reading or rendering of the meaning of this mind by another mind. In other words, every interpretation has so far a dual aspect: it at once brings two minds into quasi-social contact and distinguishes between them or contrasts them. In the light of this contrast and with reference to the direction in which it is read, the two minds are known each in the light of the other. As has already been said, the two minds in question may be related as a man's own past self is related to his present or future self. And in fact, as Peirce has pointed out, every act of interpretation has also a triadic character. For the cognitive process in question has not only a social character, but what one may call a directed `sense.' In general, when an interpretation takes place, there is an act B wherein a mental process A is interpreted, read, or rendered to a third mind. That the whole process can take place within what, from some larger point of view, is also a single mind with a threefold process going on within it has already been pointed out. Thus, when a man reflects on his plans, purposes, intents, and meanings, his present self, using the signs which memory offers as guides, interprets his past self to his future self, the cognitive process being well exemplified when a man reminds himself of his own intents and purposes by consulting a memorandum made yesterday for the sake of guiding his acts to-day. Every explicit process involving self-consciousness, involving a definite sequence of plans of action, and dealing with long stretches of time, has this threefold character. The present self interprets the past self to the future self; or some generally still more explicit social process takes place whereby one self or quasi-self has its meanings stated by an interpreter for the sake of some third self.
Thus, in brief, knowledge by interpretation is (1) an expression (by an 'interpreter') of (2) the idea or
( 158) meaning whereof some other mind gives a sign, and (3) such an expression as is addressed to some third mind, to which the interpreter thus reads or construes the sign.
3. Self-interpretation, comparison of one's own ideas, and knowledge of time.--When such interpretation goes on within the mind of an individual man, it constitutes the very process whereby, as is sometimes said, he 'finds himself,' 'comes to himself,' 'directs himself,' or 'gets his bearings,' especially with reference to time, present, past, and future. In the inner life of an individual man this third mode of cognition, therefore, appears at once in its most fundamental and simplest form as the cognitive process whose being consists in a comparison of ideas. The ideas compared here belong in one sense to the 'same self'; but they differ as the ideas of 'past self' and 'future self'; or, in various other ways, they belong to different 'quasi-minds.'
That such a process is, indeed, irreducible to pure perception, to pure conception, or to that active synthesis of the two which James has in mind when he uses the term 'idea,' readily becomes manifest if we consider what takes place when two 'ideas' are 'compared,' whether these two belong to men who are 'different individuals' or to the past, present, or future selves of. one who is, from another point of view, the same man.
An 'idea,' when the term is used in the sense which recent pragmatism has made familiar and prominent, is not a mere perception, nor a mere collection or synthesis of various perceptions, images, and other immediate data; nor yet is it a mere conception, whether simple or complex. It is, for James and his allies, a 'leading,' an 'active tendency,' 'a fulfilment of purpose,' or an effort towards such a fulfilment, an
(159) 'adjustment to a situation,' a seeking for the 'cash,' in the form of sense-data, such as may, when found, meet the requirements, or 'calls,' made by the conceptual aspect of the very idea which is in question. This concept has, in Bergson's phrase, its 'credit value.' Eventual sense-data may furnish the corresponding 'cash.' The idea is the seeking for this 'cash.' When the wanderer in the woods decides to adopt the idea that 'yonder path leads me home,' he makes an active synthesis of his concept of home and of his present sense-data. This active synthesis expressed in his idea. 'I am homeward bound,' is a 'leading,' which, if he is successful, will result in furnishing to him, when his wanderings cease, the perceptions of home which constitute the goal of his quest. This, then, is what is meant by the term 'idea' in that one of its senses which pragmatism has recently most emphasized.
In this way we may also illustrate how the cognitive process possesses the two forms or aspects which have usually been regarded as the only fundamentally distinct aspects of knowledge: perception and conception. We meanwhile illustrate that active union of these two which constitutes the 'idea' as defined by recent pragmatism. But we do not thus illustrate an aspect of cognition which is equally pervasive and significant, and which consists in the comparison of ideas. It is just this aspect of cognition upon which our present theory most insists. For by what process does the wanderer, when he reaches home, recognize that this home which he finds is the very home that he had sought? Not by the mere presence of a 'home-feeling,' not by a perception which, merely at the moment of home-coming, pays the 'cash' then required by some then present conception of home, but by a process involving a comparison of his ideas about his home, at the moment when he reaches home, with his memories of what his ideas were while he was lost in the woods and while he still inquired or sought the way home.
In order to consider what such a comparison essentially involves, it is not necessary to suppose that the act of comparison must take place in a form involving any high grade of self-consciousness, or depending upon a previous formation of an elaborate system of ideas about the self, the past, and similar objects. The essentially important fact is that whoever begins, even in the most rudimentary way, to take account of what seems to him as if it were his own past, whoever is even vaguely aware that what he has been seeking is the very object which now he finds, is not merely perceiving the present, and is not conceiving the past, and is not simply becoming aware of his present successes and disappointments as present facts--he is comparing his ideas of present success and failure with his ideas of his past efforts. This comparison is essentially an interpretation of some portion of his own past life, as he remembers that life, in the light of his present successes or disappointments, as he now experiences them. A third cognitive process is then involved. This interpretation compares at least two ideas: (1) the past idea or 'leading' (!._g., the past search for home by the path through the woods); (2) the present success or failure (e-g., the reaching home itself, or getting to the close of some stage of the wandering); and, in making this comparison, this interpretation estimates the result, perhaps in the light of one's idea of one's own future ('and henceforth I need search no more'), or perhaps in the light of one's idea of one's entire self ('I have succeeded,' or 'I am a knower of the truth,' or 'So much of the world of reality is mine'). In any case two comments may be made upon every such act of comparing two ideas and interpreting one in the light of the other.
(1) Unless such processes of comparing ideas were possible, and unless, in at least some rudimentary form, it took place, we could never make even a beginning in forming a coherent view of our own past and future, of our own selves as individuals, or of selves not our own. Our ideas both of the Ego and of the Alter
(161) depend upon an explicit process of comparing ideas. The simplest comparison of ideas--such as the case upon which recent pragmatism lays so much stress-the comparison upon which the very idea 'my success' also depends, the comparison, namely, which is expressed by saying, 'What I sought at a past moment is the very same as what, at the present moment, I now find,' is an instance of an act of interpretation, and is not reducible to the two other types of knowledge.
(2) All such processes of comparison are equally characteristic of the cognitive activity which goes on during our explicitly and literally social life and of the cognitive activity which is needed when we think about our relations to our own individual past and future. In brief, neither the individual Ego nor the Alter of the literal social life, neither past nor future time can be known to us through a cognitive process which may be defined exclusively in terms of perception, of conception, and of the ideal 'leadings' of the pragmatists. The self, the neighbour, the past, the future, and the temporal order in general become known to us through a third type of cognition which consists of a comparison of ideas--a process wherein some self, or quasi-self, or idea interprets another idea, by means of a comparison which, in general, has reference to, and is more or less explicitly addressed to, some third self or idea.
4. The relation of the three cognitive processes to our knowledge that various minds exist and to our views about what sorts of beings minds are.--The use of the foregoing classification of the types of cognitive processes appears of special importance as soon as we turn to a brief outline of some of the principal theories about the nature of mind which have played a part in the history of philosophy. Nowhere does the theory of knowledge show itself or more importance in preparing the way for an understanding of metaphysical problems than in the case of the metaphysics of mind. No attentive student of the problem of mind can easily fail at least to feel, even if he does not very
( 162) explicitly define his feeling, that in dealing with the philosophy of mind both common sense and the philosophers are accustomed to combine, sometimes in a very confused way, a reference to different more or less hypothetical beings, while the ideas that are proposed with regard to the nature of these beings are of profoundly different types.
Thus it may be a question for common sense or for a given metaphysical doctrine as to whether or not there exists a so-called soul. Now it makes a great difference for the theory of the soul whether the kind of soul which is in question is viewed as in its essence an object of a possible immediate acquaintance or perception, as an object of a possible adequate conception, or as an object whose being consists in the fact that it is to be interpreted thus or so. Unless the three kinds of cognition are clearly distinguished, the one who advances or tests a given theory of the soul does so without observing whether he himself is speaking of the soul as a possible perception, or is treating it as if it were, in its inmost nature, an object which can be known only through some adequate conception. If one has called to his attention the fact that he is speaking now in perceptual and now in conceptual terms of the mind or soul which his theory asserts to be real, he may then attempt to solve his difficulties in the way which recent pragmatism has emphasized, i.e., he may declare that his doctrine is of necessity a 'working hypothesis' about the nature of the soul, that it is, of course, in part stated in conceptual terms, but that the concepts are true only in so far as they prove to be somewhere directly verifiable in terms of immediate percepts.
Yet nowhere does recent pragmatism, in the form in which William James left it, more display its inadequacy as a theory of knowledge than in the case where it is applied to an effort to define the truth of hypotheses concerning mind, or to test such truth. For, as a fact, nobody who clearly distinguishes his neighbour's individual mind from his own expects, or
(163) can consistently anticipate, that his neighbour's mental states, or that anything which essentially belongs to the inner life or to the distinct mind of his neighbour, can ever become, under any circumstances, a direct perception of his own. For, if my neighbour's physical pains ever became mine, I should know them by immediate acquaintance only in so far as they were mine and not my neighbour's. And the same holds true of anything else which is supposed to be a fact essentially belonging to the individual mind of my neighbour. At best I can hope, with greater or less probability, to interpret correctly the meaning, the plan, or some other inner idea of the mind of my neighbour; but I cannot hope to go beyond such correct interpretation so far as to perceive my neighbour's mental states. For, if my neighbour's mental states became the immediate object of my own acquaintance, my neighbour and I would so far simply melt together, like drops in the ocean or small pools in a greater pool. The immediate acquaintance with my neighbour's states of mind would be a knowledge neither of himself as he is in distinction from me nor of myself as I am in distinction from him. For this general reason 'working hypotheses' about the interior reality which belongs to the mind of my neighbour can never be 'converted into the cash of experience.' My neighbour's mind is never a verifiable object of immediate acquaintance, precisely as it is never an abstract and universal idea. The one sort of knowledge for which recent pragmatism has no kind of place whatever is a knowledge, statable in pragmatistic terms, concerning my neighbour's mind.
James himself follows a well-known and ancient philosophical tradition by declaring that our assertion of the existence of our neighbour's mind depends upon the argument from analogy. Because of similar behaviours of our organism we regard it as by analogy probable that both our neighbour's organism and our own are vivified by more or less similar mental lives, so that we have similar experiences. But to regard or to believe in the mind of our neighbour as an
( 164) object whose existence is to be proved through an argument from analogy raises a question whose answer is simply fatal to the whole pragmatistic theory of knowledge. Surely an argument from analogy is not its own verification. For pragmatism the truth of a hypothesis depends upon the fact that its conceptual constructions are capable of immediate verification in terms of certain facts of immediate experience. But my neighbour's inner states of mind can never become for me objects of immediate acquaintance, unless they become my states of mind and not his, precisely in so far as he and I are distinct selves.
The hypothesis that our mental lives are similar may thus be suggested by analogy or may be stated in terms of analogy; but the analogy in question is essentially unverifiable in the required terms, i.e., in terms of immediate perceptions. For my neighbour can immediately perceive only his own states, while I, in so far as I am not my neighbour, can verify only my own states. From the point of view, then, of the argument from analogy, my neighbour, in observing his own states, does not verify my hypothesis in the sense in which my hypothesis about him demands verification, namely in terms of the experience of the self who makes the hypothesis. From this point of view, the problem of the mind of my neighbour remains hopeless.
It is possible, of course, to say of the foregoing argument from analogy what is also said both by common sense and by science, on the basis of a theory of truth which is in its essence conceptual and realistic. One can, of course, assert that in actual fact the mental states of my neighbour really exist and are in a certain relation which makes it true to say that they are analogous to mine. This real relation may be asserted to be as much a fact as any other fact 'in the universe. If this fact of the real analogy is granted, then it may be declared that my hypothesis to the effect that my neighbour's mind is a reality is actually true. This, however, is precisely the type of truth which William James's pragmatism undertakes to reject.
A very different appearance is assumed by the whole matter if we recognize that there is a third kind of knowledge, which is neither conceptual nor perceptual, and which is also not the sort of union of conception and perception which is completely expressible in terms of the favorite metaphor of Bergson and the pragmatists, namely, the metaphor of the conversion of conceptual credits or bank-notes into perceptual cash, i.e., into immediate data of experience. For interpretations are never verified merely through immediate data, nor through the analysis of conceptions. This is true whether I myself am the object of my own interpretation or my neighbour is in question. If we seek for metaphors, the metaphor of the conversation, already used, furnishes the best means of indicating wherein consists the relative, but never immediate, verifiability of the truth of an interpretation.
When I interpret (whether my own purposes or intents or the ideas of another man are the objects which I seek to interpret), what I first meet in experience is neither a matter of acquaintance nor a mere 'knowledge about.' What I meet is the fact that, in so far as I now understand or interpret what I call myself, I have also become aware, not immediately but in the temporal process of my mental life, that ideas have come to me which are not now my own, and which need further expression and interpretation, but which are already partially expressed through signs. Under these circumstances, what happens is that, as interpreter of these signs, I offer a further expression of what to me they seem to mean, and I make the further hypothesis that this expression makes more manifest to me both the meaning of this sign and the idea of the mind or self whereof this sign gave partial expression. Lt is of the essence of an expression which undertakes to interpret a sign that it occurs because the sign already expresses a meaning which is not just at the present moment our own, and which, therefore, needs for us some interpretation, while the interpretation which at the moment we offer is itself not complete, but requires further interpretation.
In literal conversation our neighbour utters words which already express to us ideas. These ideas so contrast with our own present ideas that, while we find the new ideas intelligible, and, therefore, view them as expressions of a mind, we do not fully know what they mean. Hence, in general, our neighbour having addressed us, we in reply ask him, more or less incidentally or persistently, whether or not this is what he means--i.e., we give him back our interpretation of his meaning, in order to see whether this interpretation elicits a new expression which is in substantial agreement with the expression which we expected from him. Our method in a conversation is, therefore, unquestionably the method of a 'working hypothesis.' But since this 'working hypothesis' refers to our neighbour's state of mind, it is never conceivably capable of direct verification.
Nor does what the pragmatists are accustomed to call the successful 'working' of this hypothesis consist in the discovery of any perceptible fact with which we get into merely immediate relation. Our interpretation of our neighbour satisfies our demands, precisely in so far as our interpretations which are never complete, and which always call for new expressions and for further interpretations, lead to a conversation which remains, as a whole, essentially 'coherent,' despite its endless novelties and unexpected incidents.
Our whole knowledge of mind, in so far as by this term we mean intelligent mind, not only depends upon, but consists in, this experience of a consistent series of interpretations, which we obtain, not merely by turning conceptual 'credits' into the 'cash of immediate acquaintance,' but by seeking and finding endlessly new series of ideas, endlessly new experiences and interpretations. This never-ended series of ideas, in so far as we can hold them before our minds, tends to constitute a connected, a reasonable, a comprehensible system of ideal activities and meanings. The essence of mental intercourse--we may at once say the essence of intelligent mental life and of all spiritual relations–
(167) not only depends upon, but consists in, this coherent process of interpretation.
Or, again, an interpretation is not a conceptual hypothesis. which can be converted into 'perceptual knowledge'; it is a hypothesis which leads us to anticipate further interpretations, further expressions of ideas, novel bits of information, further ideas not our own, which shall simply stand in a coherent connexion with one another and with what the original interpretation, as a hypothesis, had led us to expect. When I deal with inanimate nature, I may anticipate facts of perception, and then my hypothesis about these facts 'work,' in so far as the expected perceptions come to pass. But, when I deal with another mind, I do not merely expect to get definable perceptions from that mind; I expect that mind to give me new ideas, new meanings, new plans, which by contrast are known at each new stage of social experience to be not my own, and which may be opposed to my own and in many respects repellent to me.
But it is essential to the social intercourse between minds that these endlessly novel ideas and meanings should, through all conflicts and novelties and surprises, retain genuine coherence. Thus, in dealing with other minds, I am constantly enlarging my own mind by getting new interpretations, both of myself and of my neighbour's life. The contrasts, surprises, conflicts, and puzzles which these new ideas present to me show me that in dealing with them I am dealing with what in some respects is not my own mind. The coherence of the whole system of interpretations, ideas, plans, and purposes shows me just as positively that I am dealing with a mind, i.e., with something which through these expressions constantly interprets itself, while, as I deal with it, I in turn constantly interpret it, and even in and through this very process interpret myself. It will and must be observed that this Alter, with which I have to deal, both in reflecting on my own mind and in seeking for new light from my neighbour, is never a merely single or separable or
(168) merely detached or isolated individual, but is always a being which is of the nature of a community, a `many in one' and a 'one in many.' A mind knowable through interpretation is never merely a 'monad,' a single detached self; its unity, in so far as it possesses genuine and coherent unity, tends, in the most significant cases, to become essentially such as the unity which the apostle Paul attributes to the ideal Church: many members, but one body; many gifts, but one spirit (Ro 12 4ff.)--an essentially social unity, never to be adequately conceived or felt, but properly the object of what the Apostle viewed, in its practical and religious aspect, as the spiritual gift of charity, in its cognitive aspect as interpretation: pray rather that ye may interpret (1 Co 14 13).
5. Metaphysical theories of the nature of mind.-(a) Predominantly perceptual theories--The nature of mind may be defined by a given metaphysical theory mainly in terms which regard mind as best or most known through possible 'perceptions' or through possible 'acquaintance' with its nature. Such theories have been prominent throughout the whole history of human thought. They depend, first, upon ignoring the fact that what is most essential in the mind is known through the cognitive process of interpretation. They depend, further, upon making comparatively light of the effort to give any abstract conceptual description of what constitutes the essence of mind. They depend upon turning to what is sometimes called 'introspection,' or again, 'intuition,' to bring about an immediate acquaintance with mind.
Since, in general, any one who forms a predominantly perceptual idea of what mind is very naturally is not depending solely upon his own personal experience, but upon the experiences which he supposes other minds to possess, these perceptual theories of the nature of mind actually make a wide use of the reports of other people and so, more or less consciously, of arguments from analogy.
The simplest and vaguest, but in some respects the most persistent, of all theories of mental life appears, upon a largely perceptual basis, and also upon a basis of an argument from analogy, in countless forms of socalled 'animism.' Leaving aside all the historical complications, we may sum up the animistic theory of mind thus. We perceive, within ourselves, certain interesting processes which include many of our feelings, embody many of our interests, and characterize many of our activities. These activities, which in ourselves we more or less directly observe, are closely connected with the whole process of the life of the organism, i.e., of the body in whose fortunes each one of us is so interested. That which produces all these feelings, awakens in us all these interests, vitalizes our own body, and forms for each of us a centre of his own apparent world--this is the mind. The mind, then, strives and longs. It feels pain and pleasure. It prospers as the body prospers, and suffers as the body suffers.
Analogy shows that other people have such minds. These minds are as numerous as the organisms in question. They resemble one another and differ from one another, much as the organisms resemble and differ from each other. An extension of this analogy, on the basis of many motives, leads us to regard the world about us as containing many minds which are not connected with human bodies--at least in precisely the same way in which our minds are connected with our bodies. When the vast mass of superstitious beliefs which have made use of such analogies and such experiences can be more effectively controlled through the advances of the human intelligence, this primitive animism tends to pass over into theories of which we find some well-known examples in early Greek philosophies. These early Greek theories of mind appear, on a somewhat primitive and already philosophical level, as 'hylozoistic.' The world or at all events, the organic world, has life principles in it which vary as the organisms vary, and which are also of a nature
( 170) that feeling and desire reveal to our relatively immediate 'knowledge of acquaintance' with our own minds.The theories of mind of this type have played a great part in the life both of philosophy and of religion. As a general theory, animism has proved very persistent, and that for obvious reasons.
One of the Hindu Upanishads  well suggests both the origin and the logical basis--such as it is--of these theories when, in an allegory, it represents the question arising within the body as to where and what the soul most is. The question is disputed amongst the various bodily organs, each asserting itself to be the principal seat of life and also of mind. To discover which view is true, the members of the body take turns in leaving the organism. When the eyes go, blindness ensues, but life and mind continue, and so on with various other members. But when the breath starts to leave the body, all the other members together cry, 'Stay with us! You are the life, you are the soul, you are the self or Atman.' This allegory sufficiently indicates how primitive, how vague, and how stubborn is such a perceptual theory of mind when defined in terms of immediate intuition, and of a more or less pragmatic testing of various views about the physical organism.
Later in its origin, but continuing in its influence to the present day, is another perceptual theory of mind, which the later Upanishads present at length, and which, in another form, is exemplified by a notable assertion of H. Bergson in his Introduction to Metaphysics  --namely, that of one object at least we all have intuitive knowledge, this object being the self. The entire history of mysticism, the history also of the efforts to discover the nature of mind through introspection, can be summarized by means of these
( 171) instances in the Hindu Upanishads that discover the true self through the experiment with breathing, and of the latest vision of Bergson, who defines the nature of mind, and also its contrast with body, in terms of the élan vital; for all these views emphasize, in various more or less primitive, or in more or less modern, forms, essentially the same theory of mind: the essence of the mind is to be known through immediate acquaintance. That which Schopenhauer calls the will to live, that which Bergson characterizes in the terms just mentioned, that which the shamans and medicinemen of all the more intelligent tribes have sought to know, is, in every case, mind viewed as an object of possible perception.
In the history of thought such perceptual theories of mind have become more highly developed and diversified, and have assumed other and very widely influential forms, by virtue of an insistence that we have an immediate perception of what is variously called 'mental activity,' 'the active soul,' or 'the principle of individual self-hood.' Motives which as a fact are not stable in purely perceptual terms have joined with this fondness for defining mind in perceptual terms to make emphatic the assertion that this theory of mind ought to be stated in expressly 'pluralistic' terms. It has, consequently, been freely asserted that we 'immediately know' our own self to be independent, to be distinct from all other selves, and thus to be unique. Since it is also sometimes asserted that we know, or that we 'know intuitively,' upon occasion, the fact that we can never be directly acquainted with the conditions of our neighbour's mind, such perceptual theories have given rise to the so-called problem of 'Solipsism.' For, if we know mind by perception only, and if we are sure of it only when we perceive it, and if each of us can perceive only his own mind, then what proves for any one of us that there is any mind but his own? The analogy which primitive animism so freely and so vaguely used becomes, for the critical consciousness questionable. In consequence,
( 172) the problem of Solipsism has remained in modern times a sort of scandal of the philosophy of the mind.
The solution of the problem of Solipsism lies in the fact, upon which Peirce so well insisted,  that no one of us has any purely perceptual knowledge of his own mind. The knowledge of mind is not statable, in the case either of the self or of the neighbour, in terms of merely immediate acquaintance. If the truth of this proposition is once understood, the entire theory of mind, whether for metaphysics or for empirical psychology, is profoundly altered. Until this inadequacy of knowledge through acquaintance to meet the real end of human knowledge is fully grasped, it is impossible to define with success either the mind or the world, either the individual self or the neighbour.
(b) Predominantly conceptual theories.--As is the case with every highly developed doctrine, the conceptual form is very naturally assumed by any philosophical theory of mind which seeks for theoretical completeness. The conceptual theories of mind have been in history of two general types: (1) the purely conceptual, _i.e. 'the abstractly rational' metaphysical theories; and (2) the more inductive conceptual theories based upon the more or less highly developed 'empirical psychologies' of the period in which these theories have flourished. We need not enumerate these theories or give their history.
Of principal importance in their history have been (1) that type of vitalism whose most classical representative is the Aristotelian theory of mind; (2) the monistic theory of mind, which often depends not so much upon the general metaphysical tendency to define the whole universe as One, but rather upon the effort to conceive mind and matter by regarding them both as the same in substance; and (3) the various
( 173) types of monadology, which are characterized by the assertion of the existence of many real and more or less completely independent minds or selves, whose nature it is either to be themselves persons or to be beings which under certain conditions can assume the form of persons.
Of those various important theories which are expressed in the predominantly conceptual form that of Aristotle is very deeply and interestingly related to primitive animism on the one hand, while, on the other hand, it looks towards that development of the idea of the distinct individual self upon which more modern forms of monadology have depended.
Whatever special forms the conceptual theories of mind may assume, the well-known problem remains: How are these conceptions of the various mental substances, or principles, or monads, which are each time in question related to the sorts of experience which the psychologists, the students of the natural history of mind, have at any stage of knowledge discovered or may yet hope to discover? From the point of view of modern pragmatism, conceptual theories of mind might be entertained as 'working hypotheses' if they led to verification in perceptual terms.
In fact, the modern physical sciences, in conceiving the nature of matter, deal with manifold problems, but use conceptual hypotheses regarding the nature of matter which are, in a large measure, subject to pragmatic tests. Molecules and atoms and, of late, various other types of conceptual physical entities, which were formerly supposed to be incapable of becoming objects of physical experience, now appear to come within the range of the experimenter's verifications. Therefore the processes of the experimental verification of physical hypotheses have, on the whole, a direct relation to the sort of knowledge upon which the pragmatists so much insist. The 'conceptual credits' of physical hypotheses are, on the whole, verifiable in terms of the 'perceptual cash' of laboratory experience. When this
( 174) is not the case, there is a tendency towards such direct verification. Hence physical hypotheses, at least regarding what is generally called the phenomenal nature of matter, have generally proved to be topics for an inquiry within the strict realm of inductive science.
But it has been, in the past, the reproach of the conceptual theories about the nature of mind that no pragmatic test can be discovered by which one might learn what difference it would make to an observer of mental processes and, in particular, of his own mental processes whether minds are 'soul substances,' or Leibnizean monads, or not, or whether the introspective observer of his own sensations or feelings is or is not himself a Leibnizean monad or Aristotelian 'entelechy'; or again, whether he is essentially persistent and indestructible. Thus, from the pragmatic point of view, the majority of these conceptual hypotheses regarding the nature of mind show little sign of promising to prove more verifiable than they thus far have been. In consequence, the outcome of conceptual views regarding the real nature of mind has been, for many reasons, on the whole sceptical. In fact, the whole nature of mind cannot be adequately conceived, and could not be so conceived even if one's power to perceive mental processes were increased indefinitely, unless another type of cognitive processes were concerned in such an enlargement. For a mind is essentially a being that manifests itself through signs. The very being of signs consists in their demanding interpretation. The relations of minds are essentially social; so that a world without at least three minds in it--one to be interpreted, one the interpreter, and the third the one for whom or to whom the first is interpreted--would be a world without any real mind in it at all. This being the case, it might well be expected that a conceptual theory of mind would fail precisely as a perceptual theory fails. Such theories would fail because they do not view the cognitive process as it is and do not take account of that which is most of all needed in order even in the most
( 175) rudimentary fashion to grasp the nature of an intelligent mind.
(c) Theories making use of the cognitive process of the interpretation.--Despite the inadequate development of the doctrine of interpretation thus far in the history of epistemology, there have not been lacking theories regarding the nature of mind according to which mind is an object to be known through interpretation, while its manifestations lie not merely in the fact that it possesses or controls an organism, but in the fact that, whether through or apart from an organism, it expresses its purposes to other minds, so that it not merely has or is a will, but manifests or makes comprehensible it will, and not merely lives in and through itself, as a monad or a substance, but is in essence a mode of self-expression which progressively makes itself known either to its fellows or to minds above or below its own grade.
That theories of mind which are based on such a view have existed, even from very primitive times, is manifest wherever in the history of religion a consultation of oracles, discovery of the future or of the will of the gods through divination, or, in fact, any such more or less superstitious appeals to other minds, and readings or interpretations of these appeals have taken place. Primitive belief in magic arts has apparently, on the whole, a conceptual type of formulation. Therefore magic has been called the physics of primitive man. It depends upon the view that man is subject to laws which, if he could discover them, he could use for his purposes, just as we now make use of the known laws of physics for industrial purposes. The supposed realm of magic arts is thus analogous to our present realm of industrial arts. The view of pragmatism-that primitive magic is not true merely because its hypotheses regarding how to cause rain or how to cure diseases do not 'work'-- is in this case fairly adequate to express the situation both epistemologically and metaphysically.
Moreover, as we have seen, animism, in its more primitive forms, expresses a predominantly perceptual theory of mind, and whether such a theory, either of mind or of the relations between mind and the physical world, is held in some simple form by the medicineman of an obscure tribe or is impressively reiterated in a Hindu Upanishad, or is fascinatingly placed in the setting of a modern evolutionary theory by Bergson, makes comparatively little difference to the essential views of the philosophy of mind which are in question. But that view of the nature of mind which gained, apparently, its earliest type of expression when men first consulted, and hereupon more or less cautiously interpreted, the oracles of their gods has (as befits a theory of mind which is founded upon a fundamental cognitive process) persisted throughout the history of human thought. This way of viewing mind has, in fact, persisted in a fashion which enables us to distinguish its expressions with sufficient clearness from those which have had their origin either in the conceptions of primitive magic or in the perceptions which guided primitive animism.
From the point of view of the cognitive process of interpretation mind is, in all cases where it reaches a relatively full and explicit expression, equally definable in terms of two ideas--the idea of the self, and the idea of the community of selves. To an explicit recognition of what these two ideas involve a great part of the history of the philosophy of mind has been devoted. Both ideas have been subject to the misfortune of being too often viewed as reducible either to purely conceptual terms or to purely perceptual terms. If the self was defined in predominantly conceptual terms, it tended to degenerate into a substance, a monad, or a mere thing of some sort. Under the influence of a too abstract epistemology (such as the Kantian) the self also appeared as the 'logical ego,' or else as the 'pure subject.'
The fortunes of the idea of the community have been analogous. In religion this idea has proved one of the
( 177) most inspiring of the ideas which have gradually transformed tribal cults into the two greatest religions which humanity possesses--Buddhism and Christianity. In ancient philosophy the community, viewed as the soul 'writ large,' inspired some of the most fruitful philosophical interpretations of Plato, Aristotle, and the Stoics. In the general history of civilization loyalty, which is identical with the practically effective love of communities as persons that represent mind on a level higher than that of the individual, is, like the Pauline charity (which is explicitly a love for the Church universal and for its spirit), the chief and the soul of the humanizing virtues--that virtue without which all the others are but 'sounding, brass or a tinkling cymbal.' Yet, in the history of thought the idea of the community has greatly suffered, less frequently from the attempt to view it as the proper object of a direct mystical perception than from the tendency to reduce it to a purely conceptual form. As a conceptual object the 'mind of the community,' the 'corporate mind,' has tended to be thought of as an entity possibly significant in a legal or in a sociological sense, but difficult and perhaps unreal, in a metaphysical sense.
Experience shows, however, that the two ideas--the idea of the individual self and that of the community-are peculiarly adapted to interpret each the other, both to itself and to the other, when such interpretation is carried on in the spirit which the religion of Israel first made central in what undertook to be a world religion, and which the apostle Paul laid at the basis both of his philosophy of human history and of his Christology.
Modern idealism, both in the more vital and less formal expressions of Hegel's doctrine and in its recent efforts at a social interpretation of the self, of the course of human evolution, and of the problems of metaphysics, has already given a partial expression to a theory of which we tend to become clearly aware in proportion as we recognize what the cognitive process of interpretation is and how it contrasts with, and is
(178) auxiliary to, the processes of conception and perception. Only in terms of a theory of the threefold process of knowledge can we hope fully to express what is meant by that form of idealism which views the world as the `process of spirit' and as containing its own interpretation and its own interpreter.