It appears strange that so acute a writer should not have perceived the true consequences to be deduced from his observation. We never really treat a man who goes mad as becoming another personage. But if he has lost his self-control from causes by himself uncontrollable, we do not punish his criminalities, and we do divest him of his social powers; he can neither vote for Parliament, bequeath property, nor do many other acts, during the period of his affliction. But we use all means for his cure, and rejoice at his return to health and society. If a man "beside himself" were "a different person," then "tipsy he" would certainly not be "ipse he."—Yet the father of ethical science decided that the criminal drunkard deserves double meed of punishment.
To Locke's theory of Personal Identity Hamilton dedicates one more note. He gives (Reid, p. 353), an extract from Lord Kames (Essays on the Principles of Morality and Natural Religion), who pronounces his own opinion and appends some unpublished remarks of Dr. Reid. "Mr. Locke, writing on personal identity, has fallen short of his usual accuracy. He inadvertently jumbles together the identity that is nature's work, with our knowledge of it. Nay, he expresses himself sometimes as if identity had no other foundation than that knowledge. I am favoured by Dr. Reid with the following thoughts on personal identity:—
"'All men agree that personality is indivisible; a part of a person is an absurdity. A man who loses his estate, his health, an arm, or a leg, continues still to be the same person. My personal identity, therefore, is the continued existence of that indivisible thing which I call myself. I am not thought; I am not action; I am not feeling; but I think, and act, and feel. Thoughts, actions, feelings, change every moment; but self, to which they belong, is permanent. If it be asked how I know that it is permanent, the answer is, that I know it from memory. Everything I remember to have seen, or heard, or done, or suffered, convinces me that I existed at the time remembered. But, though it is from memory that I have the knowledge of my personal identity, yet personal identity must exist in nature, independent of memory; otherwise, I should only be the same person as far as my memory serves me; and what would become of my existence during the intervals wherein my memory has failed me? My remembrance of any of my actions does not make me to be the person who did the action, but only makes me know that I was the person who did it. And yet it was Mr. Locke's opinion, that my remembrance of an action is what makes me to be the person who did it; a pregnant instance that even men of the greatest genius may sometimes fall into an absurdity. Is it not an obvious corollary, from Mr. Locke's opinion, that he never was born? He could not remember his birth; and, therefore, was not the person born at such a place and at such a time.'"
When we come to Hume, the case is considerably altered. He opens the question after his own manner by asking how the fact commonly stated can be; and using the difficulty of explaining this "how" as a sufficient objection against the fact asserted. "There are some philosophers," he writes (Treatise, B. I., Part iv., Sect. 6), "who imagine we are every moment intimately conscious of what we call our self; that we feel its existence and its continuance in existence; and are certain, beyond the evidence of a demonstration, both of its perfect identity and simplicity....
"Unluckily all these positive assertions are contrary to that very experience, which is pleaded for them, nor have we any idea of self, after the manner it is here explained. For from what impression could this idea he derived?... If any impression gives rise to the idea of self, that impression must continue invariably the same, through the whole course of our lives; since self is supposed to exist after that manner. But there is no impression constant and invariable. Pain and pleasure, grief and joy, passions and sensations succeed each other, and never all exist at the same time. It cannot therefore be from any of these impressions, or from any other, that the idea of self is derived; and consequently there is no such idea.... For my part, when I enter most intimately into what I call myself, I always stumble on some particular perception or other, of heat or cold, light or shade, love or hatred, pain or pleasure. I never can catch myself at any time without a perception, and never can observe anything but the perception.... The mind is a kind of theatre, where several perceptions successively make their appearance; pass, re-pass, glide away, and mingle in an infinite variety of postures and situations. There is properly no simplicity in it at one time, nor identity in different; whatever natural propension we may have to imagine that simplicity and identity. The comparison of the theatre must not mislead us. They are the successive perceptions only, that constitute the mind; nor have we the most distant notion of the place, where these scenes are represented, or of the materials, of which it is composed."
It is curious that Hume wishing to represent Mind as a melting mist of successive perceptions, should be driven into the use of a word which implied a something continuing and permanent as affording the stage on which all passing scenes called "impressions" are enacted.
Hume next discusses the laws of association; and then proceeds (same Section sub fin.) "As memory alone acquaints us with the continuance and extent of this succession of perceptions, 'tis to be considered, upon that account chiefly, as the source of personal identity. Had we no memory, we never should have any notion of causation, nor consequently of that chain of causes and effects, which constitute our self or person. But having once acquired this notion of causation from the memory, we can extend the same chain of causes, and consequently the identity of our persons beyond our memory, and can comprehend times, and circumstances, and actions, which we have entirely forgot, but suppose in general to have existed. For how few of our past actions are there, of which we have any memory? Who can tell me, for instance, what were his thoughts and actions on the first of January, 1715, the eleventh of March, 1719, and the third of August, 1733? Or will he affirm, because he has entirely forgot the incidents of these days, that the present self is not the same person with the self of that time; and by that means overturn all the most established notions of personal identity? In this view therefore memory does not so much produce as discover personal identity, by shewing us the relation of cause and effect among our different perceptions. 'Twill be incumbent on those who affirm that memory produces entirely our personal identity, to give a reason why we can thus extend our identity beyond our memory.
"The whole of this doctrine leads us to a conclusion, which is of great importance in the present affair, viz., that all the nice and subtile questions concerning personal identity can never possibly be decided, and are to be regarded rather as grammatical than as philosophical difficulties. Identity depends on the relations of ideas; and these relations produce identity, by means of that easy transition they occasion. But as the relations, and the easiness of the transition may diminish by insensible degrees, we have no just standard by which we can decide any dispute concerning the time, when they acquire or lose a title to the name of identity. All the disputes concerning the identity of connected objects are merely verbal, except so far as the relation of parts gives rise to some fiction or imaginary principle of union, as we have already observed."
If any one feels dissatisfied with these conclusions our author is ready with his apology—"The intense view of these manifold contradictions and imperfections in human reason has so wrought upon me, and heated my brain, that I am ready to reject all belief and reasoning, and can look upon no opinion even as more probable or likely than another. Where am I, or what? From what causes do I derive my existence, and to what condition shall I return? Whose favour shall I court, and whose anger must I dread? What beings surround me? and on whom have I any influence, or who have any influence on me? I am confounded with all these questions, and begin to fancy myself in the most deplorable condition imaginable, environed with the deepest darkness, and utterly deprived of the use of every member and faculty.