All human beings by nature desire to know. A sign of this is our liking for the senses; for even apart from their usefulness we like them for themselves – especially the sense of sight, since we choose seeing above practically all the others, not only as an aid to action, but also when we have no intention of acting. The reason is that sight, more than any of the other senses, gives us knowledge of things and clarifies many differences among them. (Aristotle, Metaphysica 980a21-27)
Aristotle states that we by nature have the desire to know and supports this claim by pointing at the observation that we like the senses for themselves, apart from their usefulness. Since the argument fits the form a is X, because a is Y, it can be identified as a first-order predicate argument. In this specific case, a is instantiated by ‘all human beings’, X is instantiated by ‘by nature desire to know’, and Y is instantiated by ‘have a liking for their senses’.
All human beings (a) by nature desire to know (X), because all human beings (a) have a liking for their senses (Y)
First-order predicate arguments are further differentiated by identifying the types of statement in the conclusion and the premise. In this case, the former is a statement of fact and the latter a statement of fact, which means that we are dealing with a first-order predicate argument supporting a fact with a fact (1 pre FF).
The trivial name of first-order predicate arguments is derived from the characterization of the relationship between the predicates Y and X. In this example, having a liking for our senses (Y) is explicitly presented as a ‘sign’ for by nature desiring to know (X). We can therefore call such an argument an ‘argument from sign’.
The example is taken from the opening paragraph of Aristotle’s Metaphysics and is represented here in the translation of T. Irwin and G. Fine (1995), Aristotle – Selections. Indianapolis: Hackett.