There seem to be no special states of aversion, determined by bodily causes, and related to certain pains as our appetites to their correspondent pleasures; but most persons are liable to be thrown by the prospect of certain pains into the state of passionate aversion which we call fear, and to be thereby led to estimate such pains as worse than they would be judged to be in a calmer mood. Further, when feeling any kind of pain or uneasiness we seem liable to underrate pain of a very dissimilar kind: thus in danger we value repose, overlooking its _ennui_, while the tedium of security makes us imagine the mingled excitement of past danger as almost purely pleasurable. And again when we are absorbed in any particular pleasant activity, the pleasures attending dissimilar activities are apt to be contemned: they appear coarse or thin, as the case may be: and this constitutes a fundamental objection to noting the exact degree of a pleasure at the time of experiencing it. The eager desire, which often seems an indispensable element of the whole state of pleasurable activity, generally involves a similar bias: indeed any strong excitement, in which our thought is concentrated on a single result or group of results--whether it be the excitement of aversion, fear, hope, or suspense--tends to make us inappreciative of alien pleasures and pains alike. And, speaking more generally, we cannot imagine as very intense a pleasure of a kind that at the time of imagining it we are incapable of experiencing: as (_e.g._) the pleasures of intellectual or bodily exercise at the close of a wearying day; or any emotional pleasure when our susceptibility to the special emotion is temporarily exhausted. On the other hand, it is not easy to guard against error, as philosophers have often thought, by making our estimate in a cool and passionless state. For there are many pleasures which require precedent desire, and even enthusiasm and highly wrought excitement, in order to be experienced in their full intensity; and it is not likely that we should appreciate these adequately in a state of perfect tranquillity.