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This affords us a good example of hasty and inconclusive speculation. Surely it would be as rational to suppose that the arctic species had gained their coats as that the tropical species had lost theirs. But over-hasty conclusions are, we regret to say, the rule in Mr. Darwin's speculations as to man's genealogy. He carries that genealogy back to some ancient form of animal life somewhat like an existing larval Ascidian; and he does this on the strength of the observations of Kowalevsky and Kuppfer. He assumes at once that the similarities of structure which those observers detected are due to descent instead of to independent similarity of evolution, though the latter mode of origin is at least possible,1 and can hardly be considered improbable when we reflect on the close similarity independently induced in the eyes of fishes and cephalopods.

Quite recently, however, observations have been published by Dr. Donitz, which render it necessary, at the least, to pause and reconsider the question before admitting the Ascidian ancestry of the Vertebrate sub-kingdom.

We now come to the consideration of a subject of great importance-namely, that of man's mental powers. Are they, as Mr. Darwin again and again affirms that they are,3 different only in degree and not in kind from the mental powers of brutes? As is so often the case in discussions, the error to be combated is an implied negation. Mr. Darwin implies and seems to assume, that when two things have certain characters in common, there can be no fundamental difference between them.

1 See Professor Rolleston's Address at the Liverpool Meeting of the British Association, 1870.

* See Journal für Anatomie und Physiologie, edited by Reichert and Dubois, Berlin.

There is no fundamental difference between man and the higher mammals in their mental faculties.'-Descent of Man, vol. i. p. 35.

To avoid ambiguity and obscurity, it may be well here to state plainly certain very elementary matters. The ordinary antecedents and concomitants of distinctly felt sensations may exist, with all their physical consequences, in the total absence of intellectual cognisance, as is shown by the wellknown fact, that when through fracture of the spine the lower limbs of a man are utterly deprived of the power of feeling, the foot may nevertheless withdraw itself from tickling just as if a sensation was consciously felt. Amongst lower animals, a decapitated frog will join its hind feet together to push away an irritating object just as an uninjured animal will do. Here we have coadjusted actions resulting from stimuli which normally produce sensation, but occurring under conditions in which cerebral action does not take place. Did it take place, we should have sensations, but by no means necessarily intellectual action.

'Sensation' is not 'thought,' and no amount of the former would constitute the most rudimentary condition of the latter, though sensations supply the conditions for the existence of 'thought' or 'knowledge.'

Altogether, we may clearly distinguish at least six kinds. of action to which the nervous system ministers :

I. That in which impressions received, result in appropriate movements without the intervention of sensation or thought, as in the cases of injury above given.-This is the reflex action of the nervous system.

II. That in which stimuli from without, result in sensations through the agency of which their due effects are wrought out.-Sensation.

III. That in which impressions received, result in sensations, which give rise to the observation of sensible objects. -Sensible perception.

IV. That in which sensations and perceptions continue to coalesce, agglutinate, and combine in more or less complex

aggregations, according to the laws of the association of sensible perceptions.-Association.

The above four groups contain only indeliberate operations, consisting, as they do at the best, but of mere presentative sensible ideas in no way implying any reflective or representative faculty. Such actions minister to and form Instinct. Besides these, we may distinguish two other kinds of mental action, namely:

V. That in which sensations and sensible perceptions are reflected on by thought, and recognised as our own, and we ourselves recognised by ourselves as affected and perceiving. -Self-consciousness.

VI. That in which we reflect upon our sensations or perceptions, and ask what they are and why they are.—Reason.

These two latter kinds of action are deliberate operations, performed as they are by means of representative ideas implying the use of a reflective representative faculty. Such actions distinguish the intellect or rational faculty. Now, we assert that the full possession of all the first four (presentative) kinds of action, by no means implies the possession of the last two (representative) kinds also. All persons, we think, must admit the truth of the following propositions:

Two faculties are distinct, not in degree but in kind, if we may possess the one in perfection without that fact implying that we possess the other also. Still more will this be the case if the two faculties tend to increase in an inverse ratio. Yet this is the distinction between the instinctive and the intellectual parts of man's nature.

As to animals, we fully admit that they may possess all the first four groups of actions-that they may have, so to speak, mental images of sensible objects combined in all degrees of complexity, as governed by the laws of association. We deny to them, on the other hand, the possession of the last two kinds of mental action. We deny to them, that is,

the power of reflecting on their own existence, or of inquiring into the nature of objects and their causes. We deny that they know that they know or know themselves in knowing. In other words, we deny them reason. The possession of the presentative faculty, as above explained, in no way implies that of the reflective faculty; nor does any amount of direct operation imply the power of asking the reflective question before mentioned, as to 'what' and 'why.'

According to our above given definition, then, the faculties of men and those of other animals differ in kind; and brutes low in the scale supply us with a good example in support of this distinctness; for it is in those animals which are generally admitted to be wanting in reason-such as insects (e.g. the ant and the bee)-that we have the very summit and perfection of instinct made known to us.

We will shortly examine Mr. Darwin's arguments, and see if he can bring forward a single instance of brute action implying the existence in it of the representative reflective power. Before doing so, however, one or two points as to the conditions of the controversy must be noticed.

In the first place, the position which we maintain is the one in possession-that which is commended to us by our intuitions, by ethical considerations, and by religious teaching universally. The onus probandi should surely therefore rest with him who, attacking the accepted position, maintains the essential similarity and fundamental identity of powers, the effects of which are so glaringly diverse. Yet Mr. Darwin quietly assumes the whole point in dispute, by asserting identity of intuition where there is identity of sensation (vol. i. p. 36), which, of course, implies that there is no mental power whatever except sensation. For if the existence of another faculty were allowed by him, it is plain that the action of that other faculty might modify the effects of mere sensation in any being possessed of such additional faculty.

Secondly, it must be remembered that it is a law in all reasoning that where known causes are sufficient to account for any phenomena we shall not gratuitously call in additional causes. If, as we believe to be the case, there is no need whatever to call in the representative faculty as an explanation of brute mental action;-if the phenomena brutes exhibit can be accounted for by the presentative faculty-that is, by the presence of sensible perceptions and emotions, together with the reflex and co-ordinating powers of the nervous system;-then to ascribe to them the possession of reason is thoroughly gratuitous.

Thirdly, in addition to the argument that brutes have not intellect because their actions can be accounted for without the exercise of that faculty, we have other and positive arguments in opposition to Mr. Darwin's view of their mental powers. These arguments are based upon the absence in brutes of articulate and rational speech, of true concerted action and of educability, in the human sense of the word. We have besides, what may be called an experimental proof in the same direction. For if the germs of a rational nature existed in brutes, such germs would certainly ere this have so developed as to have produced unmistakably rational phenomena, considering the prodigious lapse of time passed since the entombment of the earliest known fossils. To this question we will return later.

We shall perhaps be met by the assertion that many men may also be taken to be irrational animals, so little do the phenomena they exhibit exceed in dignity and importance the phenomena presented by certain brutes. But, in reply, it is to be remarked that we can only consider men who are truly men—not idiots, and that all men, however degraded their social condition, have self-consciousness properly so called, possess the gift of articulate and rational speech, are capable of true concerted action, and have a perception of

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