Aristotle has the resources to solve the Conjunctive Problem of Happiness and thus to vouchsafe the necessity of ethically virtuous activity while clarifying the kind of priority that contemplation has. Among these resources is his theory of predication as articulated in the Organon, his toolkit for all sorts of philosophical inquiry. This theory allows us to understand the coherence of what have appeared to many to be fundamentally discrepant answers to the question about what kind of activity happiness is.

Aristotle’s theory of human happiness explicitly depends on the claim that intellectual contemplation is peculiar to human beings, whether it is our ergon (work, function, characteristic activity) or only part of it. But there is a notorious problem: Aristotle says that divine beings also contemplate. For this reason, many interpreters affirm the Divinity Thesis: Contemplation is not proper to human beings, for divine beings engage in it, too. The Divinity Thesis thwarts solving the Conjunctive Problem. Drawing on an analysis of what divine contemplation involves according to Aristotle, I argue that he rejects the Divinity Thesis. This opens the door to an account of what is proper to humans that is able to solve the Conjunctive Problem.

Biology and theology are interdependent theoretical sciences for Aristotle. In prominent discussions of the divine things (the stars and their unmoved movers) Aristotle appeals to the science of living things, and in prominent discussions of the nature of plants and animals Aristotle appeals to the nature of the divine. There is in fact a single continuous series of living things that includes gods, humans, animals, and plants, all of them living and, in a way, divine. Aristotle has this continuum of divine beings, and a theory of value that corresponds to it, in mind not only in key parts of his theology and natural science (including astrophysics and biology), but also in his practical philosophy. Here I can do little more than call attention to some important texts and attempt to offer a coherent account of them, without being able to enter into the usual interpretive disputes. I begin by clarifying the terms “theology” and “biology” and their place in Aristotle’s division of philosophy. Next, I discuss how Aristotle’s theology is informed by his biology, and then how his biology is informed by his theology. I end by discussing some implications of the interdependence of biology and theology for Aristotle’s ethics and exhortation to philosophy.