Near the De anima's beginning, after indicating how fine and important inquiry into the soul is, Aristotle comments about the extreme difficulty of the enterprise: “In every way and altogether it is most difficult to gain any conviction concerning it” (402a10–11). If Aristotle then manages to develop a compelling account, we must be impressed and pleased with the accomplishment. But examination of the text may prove unsettling because it seems frequently obscure, and continued study may disclose discouraging tensions and disagreements. What are we to make of this work?

Thinkers prior to Aristotle audaciously sought comprehensive understanding of the world and its prodigious array of phenomena, living beings holding special fascination for them. The tradition of the history of philosophy initiated by Aristotle suggests that philosophy very soon turned its attention from the near at hand to the wider cosmos, and only later with Socrates focused on the human life (see Metaphysics 982b11–17 and 987b1–4). In fact, however, the human being and life-bestowing soul were of interest right from the start. The first philosophical fragment, that of Anaximander (DK 12B1), compares the scheme of the universe to the system of human justice, and Anaximenes (DK 13B2) has the human soul unifying us much as the cosmos is unified. Surely Xenophanes and Heraclitus, as well as Parmenides, Empedocles, Anaxagoras, and Democritus, reflect deeply upon human life. With Socrates and Plato the reflection intensifies and perhaps turns in some new directions.