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Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: 148 CHAPTER XIX. IDEAS OF THE PLEASURABLE AND PAINFUL SENSATIONS, AND OF THE CAUSES OF THEM. We have already seen, that all sensations are capable of being revived, without that action on the organs of sense which originally produced them; and that, when so revived, we call them ideas or copies of the sensations. The sensations which are pleasurable and painful, are revived in the same manner as those which are indifferent; but, as the sensations which are pleasurable and painful form a class of sensations remarkably distinguished from sensations of the indifferent class, the ideas of the pleasurable and painful sensations form a class of ideas, no less remarkably distinguished from the ideas of the indifferent sensations. It is necessary to endeavour by a particular effort to distinguish accurately from all otherfeelings that peculiar state of consciousness, which we call the idea of a pleasurable or painful sensation; in other words, that sensation revived, after the operation upon the senses has ceased. This state of consciousness, like other states, is known only by having it. What it is felt to be, it is. We can afford, therefore, no aid to the reader in distinguishing it, otherwise than by using such expressions as seem calculated to fix his attention upon it. It is his own inward, invisible state, which only he can mark for himself. The idea of a pain or pleasure, is not a pain or pleasure. We do not say, that the idea of the hand scalded is a pain, or the idea of a sweet smell is a pleasure. But this is not very satisfactory language; for it, in reality, means little more, than that the idea of a pleasurable or painful sensation, is not a sensation. That there are some trains of ideas, however, which it is agreeable to have, others which it is disagree...