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energy. I am not unaware of the exceptions to this rule; they have been dwelt upon in the text. But these exceptions are very far from subverting the rule to the extent of classing the painful and the pleasurable stimuli under one head. I agree with Mr. Spencer that force is never lost in the animal system, and that, in the case of every sensation, we should enquire-' where is all the nervous energy gone?' but I am quite able to render a full account of the effects of a hurt; they are the destruction of the pre-existing energy of the system, the rupturing of the tissues, and the perverting of the natural functions. They are negative, or hostile influences; they put an arrest upon our movements, instead of increasing them. This arrest I look upon as the primary and proper effect of the agencies of pain; while the appearances of heightened energy that would seem to confound pain and pleasure, are but the occasional and temporary operation of another law of the animal organization.

Kant, in a passage quoted by Sir W. Hamilton (Metaphysics, ii. 472), appears to have regarded pleasure as connected with Conservation. The following sentences, separated from a number of very confusing statements in the immediate context, are to this effect: 'Pleasure is the feeling of the furtherance (Beförderung), pain of the hindrance of life. Under pleasure is not to be understood the feeling of life; for in pain we feel life no less than in pleasure-nay, even perhaps more strongly. In a state of pain, life appears long, in a state of pleasure, it seems brief; it is only, therefore, the feeling of the promotion or furtherance of life, which constitutes pleasure. On the other hand, it is not the mere hindrance of life which constitutes pain; the hindrance must not only exist, it must be felt to exist.'

Sir W. Hamilton has propounded a theory of pleasure and pain, subtantially identical with the definition given by Aristotle (Nicomachean Ethics, Book X.). It is summed up in these words: Pleasure is the reflex of the spontaneous and unimpeded exertion of a power, of whose energy we are conscious. Pain is a reflex of the overstrained or repressed exertion of such a power.' It is no part of my present plan to enter fully into the theory of pleasure and pain; the present discussion has been exclusively turned upon the physical concomitants, which in all the theories quoted by Sir W. Hamilton, are mixed up with purely mental considerations. I will only remark that the theory of Aristotle,

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VOLITION IN ANIMALS AT BIRTH.

675 as rendered by Hamilton, making pleasure the concomitant of the unimpeded energy of a natural power, faculty, or acquired habit,' by excluding passive pleasures (a warm bath, for instance), is obviously one-sided. The case is not bettered by giving to energy a meaning so wide as to include our passive sensibilities; the definition is thereby rendered so vague as to be quite worthless. The adoption of such a theory is interesting only as throwing light on the individuality of the holder.

C.-The Germs and the Development of Volition.-pp. 305, 413.

In a note (p. 415) I have given observations made upon two new-born lambs, as illustrating the origin and progress of voluntary power. I have since had opportunities of making observations on the first movements of the calf, which bore out the main points stated in the other case. It was a matter of ocular demonstration, that the new-born calf at first did not know which way to move to approach the cow, and had no notion of the udder or of its whereabouts.

I have interrogated shepherds as to the circumstances attending the birth of lambs, and especially as to their ability to find out for themselves the mother's teats. I have been told in reply, that when the ewe and the lamb are both vigorous, they come together very soon of their own accord; but if one, or other, or both, are weakly, assistance must be given, otherwise the lamb is in danger of perishing before it can find its way to the teat. This was the most pertinent statement that I could elicit, and it is strongly confirmatory of the general doctrine advanced in the text, namely, initial spontaneity working under trial and error, the successful strokes being clenched and sustained under the law of Conservation. Great physical vigour in the lamb is necessarily accompanied with an abundant spontaneity, the essential condition of a favourable start or commencement in the process of volitional acquisition.

I have stated, under the title of the principle of Self-conservation, what I deem the primitive link that connects action with feeling. This has been expressed by Mr. Spencer, with reference to the lowest forms of life, in the following terms:-' Thus, there is not a little reason to think, that all forms of sensibility to external stimuli, are, in their nascent shapes, nothing but the

modifications which those stimuli produce in that duplex process of assimilation and oxidation which constitutes the primordial life. No part of the tissue of a zoophyte can be touched, without the fluids diffused throughout the adjacent parts being put in motion, and so made to supply oxygen and food with greater rapidity. Nutritive matter brought in contact with the surface, which, in common with the rest of the body, assimilates, must cause a still greater excitement of the vital actions; and so must cause the touch of organic substance to be more promptly responded to than that of inorganic substances. A diffusion of nutritive matter in the form of an odour will tend, in a slight degree, to produce analogous effects.'-(Psychology, p. 403.)

Mr. Spencer has not, as it seems to me, made the full use of this hypothesis in his subsequent explanations of the growth of volition. Such an assumption is requisite in order to explain why certain movements, out of a great number happening, are retained by preference, so as to enter into a cohering union with definite states of feeling.

D.-Seat of revived impressions.-p. 346.

The following additional illustration, regarding the physical seat of revived impressions, is given by Wundt. 'If we look long at green light, a white surface, when we turn to it, appears red; if we look long at red light, the white surface appears green. Thus, every picture of an external object leaves behind it an after-picture, which has the same outline as the original picture, but is seen of the complementary colour of the original. Now, a picture of the fancy leaves, though generally much less intensely, an after-picture too. If, with the eye closed, a picture of very lively colour is for a long time steadily held fixed before the fancy, and the eye be then suddenly opened and turned upon a white surface, the picture of the fancy is seen upon the white ground for a short time of a colour the complement of the original. This can take place, only because the eye has been wearied by the sameness of the colour of the picture of the fancy, and needs to seek relief in its complement, just as it would do with a real coloured object before it. The experiment proves that the nervous process in both cases is identical.' Kant, also, in one of his minor works, wishing to oppose the opinion that

SEAT OF REVIVED IMPRESSIONS.

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the soul or thinking principle resides only in the brain and in one part of it, meets the argument adduced from the feeling we have in the head in hard thinking, as follows:- What causes the thinking soul to be felt chiefly in the brain, is perhaps this. All thought requires the mediation of signs, which may support the ideas to be aroused and give the necessary degree of clearness. Such companion signs for our ideas are for the most part obtained through hearing and sight, both which senses are set in action by the impressions in the brain, since their organs lie nearest to it. If, now, the rousing of these signs, called by Descartes idea materiales, be properly a stimulation of the nerves to an activity resembling that which formerly brought about the sensation, the tissue of the brain in the act of thinking will fall to be affected in harmony with former impressions, and thereby become exhausted.' Here we have a partial recognition of the theory contended for in the text.

Sir W. Hamilton maintains substantially the same view in the following passages :-'I shall terminate the consideration of Imagination proper by a speculation concerning the organ which it employs in the representation of sensible objects.' 'But experience equally proves that the intercranial portion of any external organ of sense cannot be destroyed, without a certain partial abolition of the Imagination proper. For example, there are many cases recorded by medical observers of persons losing their sight, who have also lost the faculty of representing the images of visible objects. They no longer call up such objects by reminiscence, they no longer dream of them. Now, in these cases it is found that not merely the external instrument of sight -the eye-has been disorganized, but that the disorganization has extended to those parts of the brain which constitute the internal instrument of this sense, that is, the optic nerves and thalami. If the latter, the real origin of vision, remain sound, the eye alone being destroyed, the imagination of colours and forms remains as vigorous as when vision was entire.' 'But not only sensible perceptions, voluntary motions likewise are imitated in and by the imagination. I can, in imagination, represent the action of speech, the play of the muscles of the countenance, the movement of the limbs; and, when I do this, I feel clearly that I awaken a kind of tension in the same nerves through which, by an act of will, I can determine an overt and voluntary motion of

the muscles; nay, when the play of imagination is very lively, this external movement is actually determined.'-(Metaphysics, ii., 169, 274.)

I quote farther a few sentences from Mr. Spencer's theory of Memory. 'To remember the colour red, is to have, in a weak degree, that psychical state which the presentation of the colour red produces; to remember a motion just made by the arm, is to feel a repetition, in a faint form, of those internal states which accompanied the motion-is an incipient excitement of all those nerves whose stronger excitement was experienced during the motion.'-(Psychology, p. 359.)

E.-Perception of the Material World.-p. 384.

I shall here advert to the mode of solving this great problem agreed on by some of the most distinguished philosophers of the present day.

Sir W. Hamilton has examined the subject at great length, recurring to it in many parts of his writings. I select the following quotation as sufficiently expressing his views :-' In the act of sensible perception, I am conscious of two things-of myself as the perceiving subject, and of an external reality, in relation with my sense, as the object perceived. Of the existence of both these things I am convinced; because I am conscious of knowing each of them, not mediately in something else, as represented, but immediately in itself, as existing. Of their mutual dependence I am no less convinced; because each is apprehended equally and at once, in the same indivisible energy, the one not preceding or determining, the other not following or determined; and because each is apprehended out of, and in direct contrast to, the other.'-(Reid, p. 747.)

Mr. Samuel Bailey, in his Letters on the Philosophy of the Human Mind, has exposed, with great clearness and force, the equivocations of language and confusion of ideas that have clouded the question of external perception. His own view is expressed in the following sentence-' It seems to have been only after a thousand struggles that the simple truth was arrived at, which is not by any means yet universally received—the truth that the perception of external things through the organs of

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