Book 1 / Chapter 13
Paragraph 5 - The Dual Nature of the Irrational Element
Explanation - Part By Part
"Therefore the irrational element also appears to be two-fold. For the vegetative element in no way shares in a rational principle, but the appetitive and in general the desiring element in a sense shares in it, in so far as it listens to and obeys it;"
Aristotle is breaking down the "irrational" parts of the soul into two parts. The first part, which he calls the "vegetative element," has nothing to do with reason at all—it’s completely automatic and instinctual, like the basic processes that keep us alive (e.g., digestion or growth). There’s no reasoning involved in these functions.
The second part, which includes things like desire and appetite (the "appetitive element"), is a bit different. While it’s not rational on its own, it does have the ability to listen to and obey reason. For example, you might feel the desire to overeat, but your rational mind can guide that desire and convince you to make a healthier choice. This shows how desires can, at least to some extent, be influenced or directed by rational thinking.
"this is the sense in which we speak of 'taking account' of one's father or one's friends, not that in which we speak of 'accounting for a mathematical property."
In this part, Aristotle is making an important distinction between two types of reasoning or interaction with rational principles. He contrasts the way we "take account" of emotional or personal relationships—like listening to a father or a friend—with how we "account for" something purely logical or abstract, like a mathematical property.
The former involves emotions, values, and relationships, where the desiring or emotional part of the soul might listen to and be influenced by rational arguments, much like how a child might listen to their parent. This isn't about strict logic or proof but rather guidance, persuasion, or understanding rooted in mutual respect or authority.
On the other hand, when we deal with something like mathematics, the reasoning is much stricter and objective. It operates in a completely logical and self-contained manner, without the involvement of emotions or the need for obedience or persuasion.
In essence, Aristotle is highlighting that the "irrational" part of the soul doesn't follow rational principles in the same way a mathematician follows logical proof—it "listens" and is "persuaded," like someone taking advice from a trusted figure.
"That the irrational element is in some sense persuaded by a rational principle is indicated also by the giving of advice and by all reproof and exhortation."
Aristotle is saying that even the irrational parts of our soul—like our desires and emotions—can be influenced or guided by rational thought to some degree. This is evident from the fact that we often give advice, scold, or encourage others (or ourselves) to act a certain way. These actions—advising, reproving, and exhorting—appeal to the part of us that might not strictly follow reason on its own but is still open to being "persuaded" or shaped by it. Essentially, our emotions and desires can learn to follow reason, even if they aren’t entirely rational by nature.
"And if this element also must be said to have a rational principle, that which has a rational principle (as well as that which has not) will be twofold, one subdivision having it in the strict sense and in itself, and the other having a tendency to obey as one does one's father."
Aristotle is making a distinction within the soul between two kinds of elements. He's saying that if we consider the desiring or emotional part of the soul (the part that includes things like wants, cravings, or feelings) as being connected to reason in any way, it’s important to separate things further.
First, there's the part of the soul that is fully and strictly rational. This is the part that creates logical thoughts and makes judgments—the "reasoning" part of us.
Second, there's the part of the soul that isn't rational on its own but responds to reason. This is like the part that listens to and follows guidance from the rational part, similar to how a child might listen to their father. It understands and respects reason but doesn't generate it independently.
So, when talking about our inner workings, Aristotle identifies this difference: rationality exists directly in the purely reasoning part of the soul and is present indirectly in the part that can be persuaded, influenced, or led by rational thought.