perceptions and practical inferences of animals differ fundamentally in kind from the rational or intelligent conduct of human folk, and that by no conceivable process of evolution could the one pass upwards into the other.
Wasmann regards the inclusion of those activities which result from sense-experience under the term “intelligence ” as pseudo-psychological. To modern psychologists mfr' of standing we must therefore turn. Under the head definition. ing “ Intellect or Intelligence, ” in the Dictionary of Philosophy and Psychology, G. F. Stout and ]. Mark Baldwin say: “ There is a tendency to apply the term intellect more especially to the capacity for conceptual thinking. This does not hold in the same degree of the connected word intelligence. We speak freely of ' animal intelligence, ' but the phrase animal intellect' is unusual. However, the restriction of the term to conceptual process is by no means so fixed and definite as to justify us in including it in the definition.” With respect to the word intellect ion again: “ There is a tendency to restrict the term to conceptual thinking. Ward does so definitely and consistently. Croom-Robertson, on the other hand, gives the word the widest possible application, making it cover all forms of cognitive process. On the whole, if the term is to be employed at all, Robertson's usage appears preferable, as corresponding better to the generality of the words intellect and intelligence.” It does not seem to be pseudo-psychological, therefore, to apply the term intelligence to the capacity, unquestionably possessed by animals, of profiting by sensory experience. The present writer has suggested that the term may be conveniently restricted to the capacity of guiding behaviour through perceptual processg reserving the terms intellect and reason for the so-called faculties which involve conceptual process. There are, however, advantages, as Stout 'and Baldwin contend, in employing the word in a somewhat wide and general sense. It is probably best for strictly psychological purposes to define somewhat strictly perceptual and conceptual (or ideational) process and to leave to intelligence the comparative freedom of a word to be used in general literature and therein defined by its context. It may be helprul, however, to place in tabular form the different uses above indicated:-
Perceptual Process. Conceptual Process.
I. Instinct (wider sense). Intelligence (e.g.Wasmann). 2. Sense-perception Intelligence (e.g. Mivart). 3. Intelligence (e.g. Stout and Baldwin).
4. Intelligence. Intellect and Reason
(e.g. Lloyd Morgan).
From this table it may be seen at a glance that, with such divergence of usage, the application of the word “intelligent ” to any given case of animal behaviour has in itself little psychological significance. If the psychological status of the animal is to be seriously discussed, the question to be answered is this: Are the observed activities explainable in terms of perceptual process only, or do they demand also a supplementary exercise of conceptual process? Granting that they are intelligent in the broad acceptation of the word, are they only perceptually intelligent or also conceptually intelligent P It would require more space than is at our command to make the distinction which is drawn by those who use these terms clear Pemepmal and distinct; but enough may perhaps be said to pmoew enable the general reader to grasp the salient p01ntS. It will be convenient to take a concrete case. A chick in the performance of its truly instinctive activities pecks at all sorts of 'small objects. In doing so it gains a certain amount of initial experience. Very soon it may be observed that some grubs and caterpillars are seized with avidity whenever occasion offers; while others are after a few trials let alone. Broadly speaking, we have here intelligent selection and rejection. Psychologically interpreted what is believed to take place is somewhat as follows. Each grub or caterpillar affords a visual impression or sensation. This as such is just a presentation to sight and nothing more. But in virtue of previous experience it suggests what was formerly presented to consciousness in that experience. It has meaning. An impression which carries meaning begotten of previous experience is raised to the level of a percept; and behaviour which is influenced and guided by such percepts, that is to say by impressions and the meaning for behaviour they suggest, is the outcome of perceptual process. If a dog learns to open a gate by lifting the latch, this may be due to perceptual process. Through previous experience the sight of the latch may suggest meaning for practical behaviour. His action may be simply due to the fact that the visual presentation has been directly associated with the appropriate bodily activities, and now by suggestion reinstates like activities; he may not, though on the other hand he may, exercise conceptual thought. Let us suppose that the chick;';;a, which selects certain caterpillars and rejects others process. does form concepts. What does this imply from the standpoint of psychology? Stout and Baldwin define conception as the “ cognition of a universal as distinguished from the particulars which it unifies. The universal apprehended in this way is called a concept.” If then the chick apprehends the universal “ good-for-eating ” as exemplified in the particular maggot, and the maggot as a concrete case of the abstract and universal “good-for-eating, ” it has a capacity for conceptual thought. “ There is one point in our definition, ” say Stout and Baldwin, “ which requires to be specially emphasized. Conception is the cognition of a universal as distinguished from the particulars which it unifies. The words “ as distinguished from ” are of essential importance. The mere presence of a universal element in cognition does not constitute a concept. Otherwise all cognition would be conceptual. The simplest perception includes a universal .... The universal must be apprehended in antithesis to the particulars which it unifies. ” The general, or in technical phraseology, the universal characteristic “ goodfor-eating ” is present in all that the chick practically finds to be edible; but the chick may just eat the nice caterpillars without thinking for a moment of edibility.
Few would dream of contending that the chick a few days old is capable of conceptual thought. Naive perceptual process pretty obviously suffices for an explanation of the behaviour of the little bird. But so too, it may be said, does it suffice for the explanation of much of the practical behaviour of men. If a great number of the actions of animals are only perceptually intelligent, so too are a great number of the actions of men and women. This is unquestionably the case; and it serves to bring out the distinction in value which may be assigned to the percept and the concept respectively. The value of the percept is for simple direct practical behaviour; the value of the concept is for the elaboration of systematic knowledge. Any given impression may have meaning for behaviour in a given situation which is like that which has previously developed in a certain manner; but it may also have significance for the interpretation of such situations in a conceptual scheme of thought. The sight of the sage-blossom may have meaning for the bee which has sucked the sweets contained in such Bowers; the sight of the bee in this situation may have significance for scientific interpretation as an example of the fertilization of Bowers by insects. The bee may be only perceptually intelligent; the man who observes its action may or may not be conceptually intelligent.
A good deal of human behaviour may be interpreted in terms of perceptual intelligence, and a far larger proportion of animal behaviour may be so interpreted. But some human conduct cannot be explained save as the outcome of conceptual intelligence. The question is, whether any carefully observed and well-authenticated cases of animal procedure are inexplicable in the absence of conceptual thought, and if so what concepts are necessarily involved? It is now conceded that the mere collection of anecdotes which result from casual as opposed to systematic observation can afford no satisfactory basis for an answer to this question. A solution can only be obtained by well-planned observations conducted by those who have an adequate psychological training. Even under these conditions
a criterion of the presence or absence of conceptual factors is