Full Idea
A generalisation is explanatory if and only if it is invariant.
Gist of Idea
Generalisations must be invariant to explain anything
Source
Bert Leuridan (Can Mechanisms Replace Laws of Nature? [2010], §4)
Book Reference
-: 'Philosophy of Science' [-], p.16
A Reaction
[He cites Jim Woodward 2003] I dislike the idea that generalisations and regularities explain anything at all, but this rule sounds like a bare minimum for being taken seriously in the space of explanations.