According to Aristotle, ’to live’ is said in many ways (De anima 413a22-25), but death means just one thing.
For ‘to live’ is said for anything that possesses mind, perception, motion and rest in place, and motion of nutrition and decline and growth (411a26-30)
According to Aristotle, soul accounts for all these forms of life. It unifies them in the living being.
And given its function of unifying life, the soul could be considered both in its proper simplicity of a life provider and both as a complex vital force manifested by its various powers.
Aside from Aristotle’s analysis, we might question whether the multiplicity of life does not due its unity to the unique sense of death.
The soul seems to borrow its unifying function from something that is above it. Kant’s transcendental ego is another solution for explaining the unity of life as the unity of self-conscience by appeal to a higher principle than the life of experience.
Aristotelian soul can be viewed as an intermediary between the uniqueness of death and the multiplicity of life.
We may testify the shadowy presence of death in the unifying soul if its marks are still present in mind, perception, motion, etc.
For the human beings, death seems to be present in such a way every time when the man tends to emphasize the living content of its acts that implies the use of one of the above mentioned powers. The steadiness in perceiving that appears under the more particular forms of dedication to a bodily passion undergoes the intensity of an act done for refuting its looseness in life and its total extinction in death. The man unifies himself in his passion just as an opposition to decaying or death, not in the virtue of his unifying soul. As a proof, the passional man forgets his other powers of soul, as different stories about love tell many times.
Also, when someone singularizes an idea and neglects other ones, it is a sign that he is not ready to use all the powers of souls, so that his idea cannot be a full living one, but is only a counterpart to death. In this case, it is his death as a partaker in the community of individuals who are able to hold their own ideas. Even if such ideas seem stronger in the community of speakers, they remain weak by themselves.
Therefore, one who held an idea must consider the other powers of the soul, not only the thinking and should bear in mind the fact that the unifying death is intimately conjoined to a unifying soul.