Sensation, imagery, feeling, emotion, together with pleasure, |92| unpleasure, and pain are names for the conscious characteris tics of impulses. How they may best be sorted out is a problem whose difficulty is much aggravated by the shortcomings of lan guage at this point. We speak, for instance, of pleasures and pains in the same fashion, as though they were of the same order, but, strictly, although pains as single self-sufficing modi fications of consciousness are easily enough obtainable, pleas ures by themselves do not seem to occur. Pleasure seems to be a way in which something happens, rather than an independent happening which can occur by itself in a mind. We have, not pleasures, but experiences of one kind or another, visual, audi tory, organic, motor, and so forth, which are pleasant. Similarly we have experiences which are unpleasant. If, however, we call them painful we give rise to an ambiguity. We may be saying that they are unpleasant or we may be saying that they are accompanied by pains, which is a different matter. The use of the term pleasure, as though like pain it was itself a complete experience, instead of being something which attaches to or fol lows along with or after other experiences, has led to a number of confusions; especially in those critical theses, to which objec tion has already been taken in Chapter Nine, which identify value with pleasure.