Early modern science sought to banish consideration of ends from the empirical world, in favor of purely mathematical and factual description. Kant recovered a heuristic use of teleology, especially in biology (see Kant’s Recovery of Ends), and numerous more recent biological researchers have followed suit.
It is relatively easy to see that any kind of desire (say on the part of an animal) is a desire for something that is usually more general than a concrete object that satisfies the desire. More broadly, living things can also plausibly be said to have indwelling tendencies of nutrition and reproduction.
The case of inorganic nature is a bit more challenging for us to understand this way, but where modern science sees abstract mathematical-physical laws in operation, the effect of which may be modified by various circumstances, Aristotle saw concrete material tendencies for things to develop in certain ways, subject to similar modifications. At a certain level of abstraction, observable material tendencies can be viewed as “moving” things in a way broadly analogous to desire. The heavy object “wants” to fall. This just refers back to the observed fact that heavy objects have a tendency to fall, when not impeded by something else. At a level of common-sense interpretation of experience, this does not lead to any false conclusions.
There is no reason why the mathematical-law description and the material-tendency description cannot coexist. The predictive power of mathematically formulated laws makes them invaluable for engineering applications. But for ordinary life, what we are usually interested in are qualitative distinctions that have practical significance.
Thus, in addition to rational ends, there seem to be three kinds or degrees of natural ends or endlike things: ends of desire; primitive vital ends; and endlike tendencies associated with Aristotelian matter of various kinds and descriptions. (See also Ends; Aristotelian Matter.)