Full Idea
Aristotle makes it clear that properties which belong essentially to anything have explanatory power vis-à-vis the other properties of things of that kind.
Gist of Idea
Essential properties explain in conjunction with properties shared by the same kind
Source
report of Aristotle (Metaphysics [c.324 BCE], props) by Joan Kung - Aristotle on Essence and Explanation IV
Book Reference
-: 'Philosophical Studies' [-], p.369
A Reaction
This means that explanation will always occur at the level of generalisation, leading to what we call 'laws', but some events are only explicable at the level of the individual.