  One somewhat surprising, and perhaps puzzling, feature of the Phaedo framework is this. On the one hand, Socrates evidently takes the soul to be in some way responsible for the life of any living organism, and hence presumably for all the various activities (etc.) that constitute, or are crucially involved in, any organism's life. On the other hand, he also takes it that there is a restricted class of activities that the soul is responsible for in some special way, such that it is not actually the case that the soul is responsible in this special way for all of the relevant activities that living organisms engage in.  Thus, given the idea that the soul is responsible, in some way or other, for all the life of any living organism, one would certainly expect it to be responsible, in some way or other, for (say) the desires, emotions and beliefs of organisms whose lives include such psychological states — and not just for some restricted subset of these desires, emotions and beliefs, but in fact for all of them. However, Socrates' attribution to the soul of all and only desires, emotions and beliefs of reason (to use the Republic framework) is actually quite compatible with the view that the soul is responsible for all the life-activities organisms engage in, including, of course, the desires (etc.) of what in the Republic framework is the non-rational soul. What Socrates needs is something that can certainly be supplied, some suitable articulation of the different ways in which the soul can be said to be responsible for relevant activities of a living organism. One such way is that to be capable of engaging in the activity in question at all, an organism has to be ensouled, perhaps ensouled in a certain way (for instance, in the way animals are rather than in the way plants are).  Another (stronger) way in which the soul can be responsible for an activity is directly: rather than being the thing in virtue of which the organism can do or undergo something or other (for instance, becoming thirsty and forming the desire to drink on that basis), the soul can also perform activities in its own right (for instance, contemplating mathematical truths). So, to restate somewhat more clearly: the Phaedo's conception of soul is narrower than our concept of mind in the following way. The range of activities (etc.) that the soul is directly responsible for, and which may be described as activities of the soul strictly speaking, is significantly narrower than the range of mental activities. It does not include all of a person's desires, nor need it include all emotional responses, or even all beliefs. One plainly could not have (for instance) ‘bodily’ desires such as hunger and thirst without being ensouled, but that does not mean that it must be the soul itself that forms or sustains such desires.  