We come now to explain the direct passions，or the impressions，which arise imme-diately from good or evil，from pain or pleasure。Of this kind are，desire and aversion，grief and joy，hope and fear。
Of all the immediate effects of pain and pleasure，there is none more remarkable than the WILL；and tho，properly speaking，it be not comprehended among the pas-sions，yet as the full understanding of its nature and properties，is necessary to the ex-planation of them，we shall here make it the subject of our enquiry。I desire it may be observ d，that by the will，I mean nothing but the internal impression we feel and are conscious of，when we knowingly give rise to any new motion of our body，or new per-ception of our mind。This impression，like the preceding ones of pride and humility，love and hatred，tis impossible to define，and needless to describe any farther；for which reason we shall cut off all those definitions and distinctions，with which philoso-phers are wont to perplex rather than dear up this question；and entering at first upon the subject，shall examine that long disputed question concerning liberty and necessity；which occurs so naturally in treating of the will。