Classical Texts in Psychology
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Outlines of Psychology
Wilhelm Max Wundt (1897)
III. INTERCONNECTION OF PSYCHICAL COMPOUNDS.
§ 17. APPERCEPTIVE COMBINATIONS.
1. Associations in all their forms and also the closely related processes of fusion that give rise to psychical compounds, are regarded by us as passive experiences, because the feeling of activity, which is characteristic for all processes of volition and attention, never appears except inconnection with the apperception of the completed product, presented as a result of the combination (cf. p. 217). Associations are, accordingly, processes that can arouse volitions, [p. 249] but are not themselves directly influenced by volitions. This is, however, the criterion of a passive process.
The case is essentially different with the second kind of combinations that are formed between different psychical compounds and their elements, the apperceptive combinations. Here the feeling of activity with its accompanying variable sensations of tension does not merely follow the combinations as an after-effect produced by them, but it precedes them so that the combinations themselves are immediately recognized as formed with the aid of the attention. In this sense they are called active experiences.
2. Apperceptive combinations include a large number of psychical processes that are distinguished in popular parlance under the general terms thinking, reflection, imagination, understanding, etc. These are all regarded as higher psychical processes than sense-perceptions or pure memory-processes, still, they axe all looked upon as different from one another. Especially is this true of the so-called functions of imagination and understanding. In contrast with this loose view of popular psychology and of the faculty-theory, which followed in its tracks, association-psychology sought to find a unitary principle by subsuming the apperceptive combinations of ideas also under the general concept of association, at the same time limiting the concept, as noted above (p. 224), to successive association. This reduction to association was effected either by neglecting the essential subjective and objective distinguishing marks of apperceptive combinations, or by attempting to avoid the difficulties of an explanation, through the introduction of certain supplementary concepts taken from popular psychology. Thus, "interest" or "intelligence" was credited with an influence on associations. Very often this view was based on the erroneous notion that the recognition of certain distinguishing features in apperceptive combinations [p. 250] and associations meant the assertion of an absolute independence of the former from the latter. Of course, this is not true. All psychical processes are connected with associations as much as with the original sense-perceptions. Yet, just m associations always form a part of every sense-perception and in spite of that appear in memory-processes as relatively independent processes, so apperceptive combinations are based ,entirely on associations, but their essential attributes are not traceable to these associations.
3. If we try to account for the essential attributes of apperceptive combinations, we may first of all divide the psychical processes that belong to this class into simple and complex apperceptive functions. The simple functions are those of relating and comparing, the complex those of synthesis and analysis.
A. SIMPLE APPERCEPTIVE FUNCTIONS.
(Relating and Comparing.)
4. The most elementary apperceptive function is the relating of two psychical contents to each other. The grounds for such relating is always given in the single psychical compounds and their associations, but the actual carrying out of the process itself is a apperceptive activity through, which the relation itself assumes a special conscious content distinct from the contents which are related, though indeed inseparably connected with them. For example, when we recognize the identity of an object with one perceived before, or when we are conscious of a definite relation between a remembered event and a present impression, there is in both cases a relating apperceptive activity connected with the associations.
So long as the recognition remains a pure association, the process of relating is limited to the feeling of familiarity that [p. 251] follows the assimilation of the new impression either immediately or after a short interval. When, on the contrary, apperception is added to association, this feeling is supplied with a clearly recognized ideational substratum. The earlier perception and the new impression are separated in time and then brought into a relation of identity on the basis of their essential attributes. The case is similar when we are conscious of the motives of a memory-act. This also presupposes that a comparison of the memory-image with the impression that occasioned it, be added to the merely associative process which gave rise to the image. This, again, is a process that can be brought about only through active attention.
5. Thus, the relating function is brought into activity through associations, wherever they themselves or their products are made the objects of voluntary observation. This function is always connected, as the examples mentioned show, with the function of comparing, so that the two must be regarded as interdependent partial functions. Every act of relating includes a comparison of the related psychical contents, and a comparison is, in turn, possible only through the relating of the contents compared with one another. The only difference is that in many cases the comparison is completely subordinated to the end of reciprocally relating the contents, while in others it is in itself the end. We speak of a process of relating in the strict sense in the first case, and of a process of comparing in the second. I call it relating when I think of a present impression as the reason for remembering an earlier experience; I call it comparing, on the other hand, when I establish certain definite points of agreement or difference between the earlier and the present event.
6. The process of comparing is, in turn, made up of two elementary functions which are as a rule intimately interconnected: of the perception of agreements on the one hand, [p. 252] and of differences on the other. The erroneous view still frequent acceptance that the existence of psychical elements and compounds is the same as their apperceptive comparison. The two are to be held completely apart. Of course, there must be agreements and differences in our psychical processes themselves, or we could not perceive them; still the comparing activity by which we perceive, is different from the agreements and differences themselves and additional to them.
7. Psychical elements, the sensations and simple feelings, are compared in regard to their agreements and differences and thus brought into definite systems, each of which contain such elements as are closely related. Within such a system, especially a sensational system, two kinds of comparison are possible: that in respect to quality, and that in respect to intensity. Then, too, a comparison between grades of clearness is possible when attention is paid to the way in which the elements appear in consciousness. In the same way comparison is applied to intensive and extensive psychical compounds. Every psychical element and every psychical compound, in so far as it is a member of a regular graded system, constitutes a psychical quantity. A determination of the value of such a quantity is possible only through its comparison with some other quantity of the same system. Quantity is, accordingly, an original attribute of every psychical element and compound. It is of various kinds, as intensity, quality, extensive (spacial and temporal) value, and, when the different states of consciousness are considered, clearness. But the determination of quantity can be effected only through the apperceptive function of comparison.
8. Psychical measurement differs from physical measurement in the fact that the latter may be carried out in acts of comparison separated almost indefinitely in time, because its objects are relatively constant. For example, [p. 253] we can determine the height of a certain mountain to-day with a barometer and then after a long time the height of another mountain and if no sensible changes in the configuration of the land have taken place in the interval, we can compare the results of our two measurements. Psychical compounds, on the other hand, are not relatively permanent objects, but continually changing processes, so that we can compare two such psychical quantities only under the condition that they axe presented in immediate succession. This condition has as its immediate corollaries: first, that there is no absolute standard for the comparison of psychical quantities, but every such comparison stands by itself and is of merely relative value; secondly, that finer comparisons are possible only between quantities of the same dimension, so that a transfer analogous to that by which the most widely separate physical quantities, such as periods of time and physical forces, are reduced to spacial quantities of one dimension, are out of the question in psychical comparisons.
9. It follows that not every relation between psychical quantities can be established by direct comparison, but this is possible only for certain particularly favorable relations. These favorable cases are 1) the equality between two psychical quantities, and 2) the just noticeable difference between two such quantities, as, for example, two sensational intensities of like quality, or two qualities of like intensity belonging to the same dimension. As a somewhat more complex case which still lies within the limits of immediate comparison we have 3) the equality of two differences between quantities especially when these quantities belong to contiguous parts of the same system. It is obvious that in each of these three kinds of psychical measurements the two fundamental functions in apperceptive comparison, the perception of agreements and of differences, are both applied together. In the [p. 254] first case the second of two psychical quantities A and B is gradually varied until it agrees for immediate comparison with A. In the second case A and B are taken equal at first and then B is changed until it appears either just noticeably greater or just noticeably smaller than A. Finally, the third case is used to the greatest advantage when a whole line of psychical quantities, as, for example, of sensational intensifies, extending from A as a lower to C as an upper limit, is so divided by a middle quantity B, which has been found by gradual variations, that the partial distance AB is apperceived as equal to BC.
10. The most direct and most easily utilizable results derived from these methods of comparison are given by the second method, or the method of minimal differences as it is called. The difference between the Physical stimuli which corresponds to the just noticeable difference between psychical quantities is called the difference-threshold of the stimulus. The stimulus from which the resulting psychical process, for example, a sensation, can be just apperceived, is called the stimulus-threshold. Observation shows that the difference-threshold of the stimulus increases in proportion to the distance from the stimulus-threshold, in such a way that the relation between the difference-threshold and the absolute quantity of the stimulus, or the relative differ threshold, remain constant. If, for example, a certain sound whose intensity is 1 must be increased 1/3 in order that the sensation may, be just noticeably greater, one whose intensity is 2 must be increased 2/3, one 3, 3/3, etc., to reach the difference-threshold. This law is called Weber's law, after its discoverer E. H. Weber. It is easily understood when we look upon it as a law of apperceptive comparison. From this point of view it mull obviously be interpreted to mean that psychical quantities are compared according to their relative values. [p. 255]
This view that Weber's law is an expression of the general law of the relativity of psychical quantities, assumes that the psychical quantities that are compared, themselves increase in proportion to their stimuli within the limits of the validity of the law. It has not yet been possible to demonstrate the truth of this assumption on its physiological side, on account of the difficulties of measuring exactly the stimulation of nerves and sense-organs. Still, we have evidence in favor of it in the psychological experience that in certain special cases, where the conditions of observation lead very naturally to a comparison of absolute differences in quantity, the absolute difference threshold, instead of the relative threshold, is found to be constant. We have such a case, for example, in the comparison, within wide limits, of minimal differences in pitch. Then, too, in many cases where large differences in sensations are compared according to the third method described above (p. 254), equal absolute stimuli-differences, not relative differences, are perceived as equal. This shows that apperceptive comparison follows two different principles under different conditions: a principle of relative comparison that finds its expression in Weber's law and must be regarded as the more general, and a principle of absolute comparison of differences which takes the place of the first under special conditions which favor such a form of apperception.
10 a. Weber's law has been shown to hold, first of all, for the intensity of sensations and then, within certain limits, for the comparison of extensive compounds, especially temporal ideas, also, to some extent, for spacial ideas of sight and for motor ideas. On the other hand, it does not hold for the spacial ideas of external touch, obviously on account of the complexity of the local signs (p. 105); and it can not be verified for sensational qualities. In fact, for the comparison of pitches the absolute, not the relative difference-threshold is constant within wide limits. Still, the scale of tonal intervals is relative, for every interval corresponds to a [p. 256] certain ratio between the number of vibrations (for example, an octave 1 : 2, a fifth 2 : 3, etc.). This is probably due to the relationship between clangs which is due to the relation of the fundamental tone to its overtones (comp. p. 95 sq.). Even where an absolute comparison takes place instead of a comparison according to Weber's law of relativity, we must not, of course, confuse this with the establishment of an absolute measure. That would presuppose an absolute unit, that is, the possibility of finding a constant standard, which, as noted above (p. 253), is in the psychical world impossible. Absolute comparison must take the form of a recognition of the equality of equal absolute difference. This is possible in the various single cases without a constant unit. Thus, for example, we compare two sensational lines AB and BC according to their relative values, when we think in both cases of the relation of the upper to the lower extreme sensation. In such a case we judge AB and BC to be equal when B/A = C/B (Weber's law). On the other hand, we compare A B and B C according to their absolute values when the difference between C and B in the single sensational dimension in question appears equal to that between B and A, that is, when C - B = B - A (law of proportionality). Weber's law has sometimes been regarded as the expression of the functional relation between sensation and stimulus, and it has been assumed that the law holds for infinitely small changes on both sides. On this basis there has been given to it the mathematical form of the logarithmic function: sensation increases in proportion to the logarithm of the stimulus (Fechner's psycho-physical law).
The methods for the demonstration of Weber's law, of relations between psychical quantities, whether elementary compound, are usually called psycho-physical methods. is unsuitable, however, because the fact that physical here employed is not unique, but holds for all the experimental psychology. They could better be capable, for the measurement of psychical quantities". With these methods it is possible to follow one of two courses in relations mentioned as favorable for judgment. A direct mode of procedure is as follows: one of two psychical quantities A and B, as, for example, A is kept constant, and B is [p. 257] gradually varied until it stands in one of the relations mentioned, that is, either equals A or is just noticeably greater or smaller, etc. These are the adjustment-methods. Among these we have as the method most frequently applied and that which leads most directly to conclusions, the "method of minimal changes", and then as a kind of modification of this for the case of adjustment until equality is reached, the "method of average error". The second mode of procedure is to compare in a large number of cases any two stimuli, A and B, which are very little different, and to reckon from the number of cases in which the judgments are A = B, A > B, A < B, the position of the relations mentioned, especially the difference-threshold. These are the reckoning-method. The chief of these is the method known as that of "right and wrong cases". It would be more proper to call it the "method of three cases" (equality, positive difference, and negative difference). Details as to this and the other methods belong in a special treatise on experimental psychology.
There are two other interpretations of Weber's law still met with besides the psychological interpretation given above; they may be called the physiological and the psycho-physical theories. The first derives the law from hypothetically assumed relations in the conduction of excitations in the central nervous system. The second regards the law as a specific law of the "interaction between body and mind". The physiological interpretation is entirely hypothetical and in certain cases, as, for example, for temporal and spacial ideas, entirely inapplicable. The psycho-physical interpretation is based upon a view of the relation of mind which must be rejected by the psychology of to-day (cf. § 22, 8).
11. As special cases in the class of apperceptive comparisons generally falling under Weber's law we have the comparison of quantities that are the relatively greatest sensational differences or, when dealing with feelings, opposites. The phenomena that appear in such cases are usually gathered up in the class-name contrasts. In the department where contrasts have been most thoroughly investigated, in residual sensations, there is generally an utter lack of discrimination [p. 258] between two phenomena which are obviously entirely in origin, though the results are to a certain extent related. We may distinguish these a physiological and psychological, contrasts. Physiological contrasts are closely connected with. the phenomena of after-images, perhaps they are the same (p. 68 sq.). Psychological contrasts are essentially different; they are usually pushed into the background by the stronger physiological contrasts when the impressions are more intense. They are distinguished from the physiological by two important characteristics. First, they do not reach their greatest intensity, when the brightness and saturation are greatest, but when they are at the medium stages, where the eye is most sensitive to changes in brightness and saturation. Secondly, they can be removed by comparison with an independent object. Especially the latter characteristic shows these contrasts to be unqualifiedly the products of comparisons. Thus, for example, when a grey square is laid on a black ground and close by a similar grey square is laid on a white ground and all is covered with transparent paper, the two squares appear entirely different; the one on the black ground looks bright nearly white, that on the white ground looks dark, nearly, black. Now after-images and irradiations are very weak when, the brightness of the objects is small, so that it may assumed that the phenomenon described is a, psychological contrast. If, again, a strip of black cardboard which is covered with the transparent piper., and therefore exactly the same grey as the two squares, is held in way that it connects the two squares the contrast is removed entirely, or, at least, very much diminished. If in this experiment a colored ground is used instead of the achromatic, the grey square will appear very clearly in the appropriate complementary color. But here, too, the contrast can be made to disappear through comparison with an independent grey object. [p.259]
12. Psychical contrasts appear also in other spheres of sensation so far as the conditions for their demonstration are favorable. They are also especially marked in the case of feelings and may arise under proper conditions in the case of spacial and temporal ideas. Sensations of pitch are relatively most free, for most persons have a well developed ability to recognize absolute pitch and this tends to overcome contrast. In the case of feelings the effect of contrast is intimately connected with their general attribute of developing toward certain opposites. Pleasurable feelings especially are intensified by unpleasant feelings immediately preceding, and the same holds for many feelings of relaxation following feelings of strain, as, for example, a feeling of fulfilment after expectation. The effect of contrast in the case of spacial and temporal ideas is most obvious when the same spacial or temporal interval is compared alternately with a longer and with a shorter interval. In the two cases the interval appears different, in comparison with the shorter it appears greatest in comparison with the longer, smaller. Here too the contrast between spacial ideas can be removed by bringing an object between the contrasted figures in such a way that it is possible easily to relate them both to it.
13.We may regard the phenomena that result from the apperception of impressions whose real character differs from that expected, as special modifications of psychical contrast. For example, we are prepared to lift a heavy weight, but in the actual lifting of the weight it proves to be lighter, or the reverse takes place and we lift a heavy weight instead of a light one as we expected: the result is that in the first case we underestimate, in the second overestimate the real weight. If a series of exactly equal weights of different sizes are made so that they look like a set of weights varying regularly from a lighter to a heavier, they will appear to be different in [p. 260] weight when raised. The smallest will seem to be the heaviest and the largest to be the lightest. The familiar association that. the greater volume is connected with the greater mass aids the contrast. The varying estimations of the weight, however, is the result of the contrast between the real and the expected sensation.
B. COMPLEX APPERCEPTIVE FUNCTIONS.
(Synthesis and Analysis.)
14. When the simple processes of relating and comparing are repeated and combined several times, the complex psychical functions of synthesis and analysis arise. Synthesis is primarily the product of the relating activity of apperception, analysis of the comparing activity.
As a combining function apperceptive synthesis is based upon fusions and associations. It differs from the latter in the fact that some of the ideational and affective elements that are brought forward by the association are voluntarily emphasized and others are pushed into the background. The motives of the choice can be explained only from the whole previous development of the individual consciousness. As a result of this voluntary activity the product of this synthesis is a complex whole whose components all come from former sense-perceptions and associations, but in which the combination of these components usually varies more or less from the actual impressions and the combinations of these impressions that, are immediately presented in experience.
The ideational elements of a compound thus resulting, from apperceptive synthesis may be regarded as the substratum for the rest of its contents, and so we call such a compound in general an aggregate idea. When the combination of the elements is peculiar, that is, markedly different from the products of the fusion and associations, the aggregate idea and each of its relatively independent ideational components [p. 261] is called an idea of imagination or image of imagination. Since the voluntary synthesis of elements may vary more or less, according to the character of the motives that gave rise to it, from the combinations presented in sense-perception and association, it is obvious that practically no sharp line of demarcation can be drawn between images of imagination and those of memory. But we have a more essential mark of the apperceptive process in the positive characteristic of a voluntary synthesis than in the negative fact that the combination does not correspond in character to any particular sense-perception. This positive characteristic gives also the most striking external difference between images of imagination and those of memory. It consists in the fact that the sensational elements of an apperceptive compound are much more like those of an immediate sense-perception in clearness and distinctness, and generally in completeness and intensity. This is easily explained by the fact that the reciprocally inhibitory influences which the uncontrolled associations exercise on one another, and which prevent the formation of fixed memory-images, are diminished or removed by the voluntary emphasizing of certain particular ideational compounds. It is possible to mistake images of imagination for real experiences. With memory-images this is possible only when they become images of imagination, that is, when the memories are no longer allowed to arise passively, but are to -some extent produced by the will. Generally, too, there are voluntary modifications in them or a mixing of real with imagined elements. All our memories are therefore made up of "fancy and truth" . Memory-images change under the influence of our feelings and volition to images of imagination, and we generally deceive ourselves with their resemblance to real experiences. [p. 262]
15. From the aggregate ideas thus resulting from apperceptive synthesis there arise two forms of apperceptive activity in the opposite direction of analysis. The one is known in popular parlance as activity of the imagination, the second as activity of the understanding. The two are by no means different, as might be surmised from these names, but closely related and almost always connected with each other. Their fundamental determining motives are what distinguish them first of all and condition all their secondary differences as well as the reaction that they exercise on the synthetic function.
In the case of the activity of "imagination" the motive is the reproduction of real experiences or of those analogous to reality. This is the earlier form of apperceptive analysis and rises directly from associations. It begins with a more or less comprehensive aggregate idea made up of a variety of ideational and affective elements and embracing the general content of a complex experience in which the single components are only indefinitely distinguished. The aggregate idea is then divided in a series of successive acts into a number of more definite, connected compounds partly spacial, partly temporal in character. The primary voluntary synthesis is thus followed by analytic acts which may in turn give rise to the motives for a new synthesis and thus to a repetition of the whole process with a partially modified or more limited aggregate idea.
The activity of imagination shows two stages of development. The first is more passive and arises directly from the ordinary memory-function. It appears continually in the train of thought, especially in the form of an anticipation of the future, and plays an important part in psychical development as an antecedent of volitions. It may, however, in an analogous way, appear as a representation in thought of imaginary situations or of successions of external phenomena. The second, or active, stage of development is under the influence of a fixed idea [p. 263] of some end, and therefore presupposes a high degree of voluntary control over the images of imagination, and a strong interference, partly inhibitory, partly selective, with the memory-images that tend to push themselves into consciousness without voluntary action. Even the first synthesis of the aggregate idea is more systematic. An aggregate idea, when once formed, is held more firmly and subjected to a, more complete analysis into its parts. Very often these parts themselves are subordinate aggregate ideas to which the same process of analysis is again applied. In this way the principle of organic division according to the end in view governs all the products and processes of active imagination. The productions of art show this most clearly. Still, there are, in the ordinary play of imagination, the most various intermediate stages between passive imagination, or that which arises directly from memory, and active imagination, or that which is directed by fixed ends.
16. In contrast with this reproduction of real experiences or of such as may be thought of as real, which constitutes the content of the apperceptive functions that we include under the concept "imagination", the fundamental motive of the "understanding" is the perception of agreements and differences and other derived logical relations between consent of experience. Understanding also starts with aggregate ideas in which a number of experiences that are real or may he ideated as real, are voluntarily set in relation to one another and combined to a unitary whole. The analysis that takes place in this case, however, is turned by its fundamental motive in a different direction. It consists not merely in a clearer grasp of the single components of the aggregate idea, but in the establishment of the manifold relations in which these components stand to each other and which we may discover through comparison. As soon as such analyses have been made [p. 264] several times, results of the relating and comparing processe~s gained elsewhere can be employed in any particular case.
As a result of its more strict application of the elementary relating and comparing functions, the activity of understanding follows definite rules even in its external form, especially when it is highly developed. The principle that holds in general for imagination and even for mere remembering, that the relations of different psychical contents which are apperceived are presented, not simultaneously, but successively, so that in every case we pass on from one relation to a succeeding -- this principle becomes for the activity of understanding, a rule of discursive division of aggregate ideas. It is expressed in the law of the duality of the logical forms of thought, according to which analysis resulting from relating comparison divides the content of the aggregate idea into two parts, subject and predicate, and may then separate each of these parts again once or several times. These second divisions give rise to grammatical forms that stand in a logical relation analogous to that of subject and predicate, such as noun and attributive, verb and object, verb and adverb. In this way the process of apperceptive analysis results in judgment.
For the psychological explanation of judgment it is of fundamental importance that it be regarded, not as a synthetic, but as an analytic function. The original aggregate ideas that are divided by judgment into their reciprocally related components, are exactly like ideas of imagination. The products of analysis that result are, on the other hand, not at in the case of imagination, images of more limited extent greater clearness, but conceptual ideas, that is ideas which stand, with regard to other partial ideas of the same whole, in some one of those relations which are discovered through the general relating and comparing functions. If we call the [p. 265] aggregate idea which is subjected to such a relating analysis a thought, then a judgment is a division of this thought into its components, and a concept is the product of such a division.
17. Concepts found in this way are arranged in certain general classes according to the character of the analyses that took place. These classes are the concepts of objects, attributes, and states. Judgment, as a division of the aggregate idea, sets an object in relation to its attributes or states, or various objects in relation to one another. Since a single concept can never, strictly speaking, be thought of by itself, but is always connected in the whole idea with one or more other concepts, the conceptual ideas are strikingly different from the ideas of imagination because of the indefiniteness and variableness of the former. This indefiniteness is essentially increased by the fact that a single concept may exist in an unlimited variety of modifications, since concepts which result from different cases of like judgment, may form components of many ideas that differ in their concrete characters. Such general concepts constitute, on account of the wide application of relating analysis to different contents of judgment, the great majority of all concepts; and they have a great number of corresponding single ideational contents. It becomes necessary, accordingly, to choose a single idea as a representative of the concept. This gives the conceptual idea a greater definiteness. At the same time there is always connected with this idea the consciousness that it is merely a representative. This consciousness generally takes the form of a characteristic feeling. This conceptual feeling may be traced to the fact that obscure ideas, which have the attributes that make them suitable to serve as representations of the concept, tend to force themselves into consciousness in the form of variable memory images. As evidence of this we have the fact that the feeling is very intense so [p. 266] long as any concrete image of the concept is chosen as its representative, as, for example, when a particular individual stands for the concept man, while it disappears almost entirely so soon as the representative idea differs entirely in content from the objects included under the concept. Word-ideas fulfil this condition and that is what gives them their importance as universal aids to thought. These aids are furnished to the individual consciousness in a finished so that we must leave to social psychology the question of the psychological development of the processes of thought active in the formation of language (comp. § 21, A).
18. From all that has been said it appears that the activities of imagination and understanding are not specifically different, but interrelated. inseparable in their rise and manifestations, and based at bottom on the same fundamental functions of apperceptive synthesis and analysis. What was true of the concept "memory" holds also of the concepts "understanding" and "imagination": they are names, not of unitary forces or faculties, but of complex phenomena made up of elementary psychical processes of the usual, not of a specific, distinct kind. Just as memory is a general concept for certain associative processes, imagination and understanding are general concepts for particular forms of apperceptive activity. They have a certain practical value as ready means for the classification of an endless variety of differences in the capacity of various persons for intellectual activity. Each class thus found may in turn contain an endless variety of gradations and shades. Thus, neglecting the general differences in grade, we have as the chief forms of individual imagination the perceptive and the combining forms; as the chief form of understanding, the inductive and deductive forms, the first being mainly concerned with the single logical relations and their combinations, the second more with general con- [p. 267] cepts and their analysis. A person's talent is his total capacity relating from the special tendencies of both his imagination and understanding.