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 other feelings 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. 190 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 disagreeable, is one among the most familiar facts of our nature. There is, therefore, a distinction among ideas, analogous to that of pleasurable and painful among sensations.
It is difficult to think of any one sensation by itself; because each is so combined with others, that the idea of one can never present itself, but in company with more. This is peculiarly the case with sensations of the pleasurable and painful kinds: and hence the cause of the indistinctness, which seems to accompany the idea of any of those sensations, when we endeavour to take it apart, and consider what it is in itself.
An idea is the revival of a former state of feeling. The first thing which I have to consider is, what is my precise state of consciousness, when I receive a pleasurable or painful sensation.
When the sensation was present, suppose a painful one, it was a state of consciousness, so interesting to me, that it was important to find a mark for it. I 191 called it Pain. It is a state of consciousness known to every man by his having had it, and it can be known by no other means. We call it by various names; an odious state, a disagreeable state, and so on; but these are only several modes of marking what is felt, and tell to no man anything more than his feeling has told. Except for his own knowledge of his own feeling, the words would be utterly without a meaning.