Book 1 / Chapter 13
Paragraph 2 - The Rational and Irrational Elements of the Soul
Explanation - Part By Part
"Some things are said about it, adequately enough, even in the discussions outside our school, and we must use these;"
Here, Aristotle is acknowledging that certain ideas or discussions about the soul—specifically the division of the soul into parts—have already been addressed by others outside of his own philosophical school. By "outside our school," he refers to thinkers or traditions not directly connected to his teachings or the Peripatetic school. He suggests that these external discussions are sufficiently "adequate" or insightful on this point, meaning he finds value in them and is willing to incorporate them into his own analysis. This reflects a pragmatic attitude: even if ideas originate elsewhere, their usefulness justifies their inclusion in his exploration of virtue and the soul.
"e.g. that one element in the soul is irrational and one has a rational principle."
Aristotle is explaining that the human soul has two fundamental aspects: one part is irrational and the other part is rational. The irrational part of the soul deals with instincts, desires, and passions—things that do not involve reasoning. Meanwhile, the rational part of the soul is capable of logical thought, deliberation, and making moral judgments. These two aspects of the soul play a central role in understanding human behavior, virtue, and ultimately happiness. Aristotle emphasizes this distinction because it helps set the foundation for exploring how humans develop virtue and live a good life.
"Whether these are separated as the parts of the body or of anything divisible are, or are distinct by definition but by nature inseparable, like convex and concave in the circumference of a circle, does not affect the present question."
Aristotle is diving into the structure of the soul, noting that there’s a fundamental distinction between the rational and the irrational parts of the soul. However, he raises a question about how these parts are related. Are they physically distinct and separate, like parts of a body (e.g., arm and leg), or are they inseparable in nature, though different in concept—like the convex (outward-curving) and concave (inward-curving) sides of a circle, which exist together but represent opposing characteristics?
Ultimately, Aristotle says this distinction—whether they are physically separate or conceptually distinct but inseparable—doesn’t really matter for the context of his current discussion. His focus is on the functional difference between these parts of the soul, not on how they are integrated structurally. This allows him to proceed with his exploration of how human virtue and reason operate within the framework of this division in the soul.