Full Idea
It is often easier to say what a factor would explain than it is to say what it would cause.
Gist of Idea
Explanations may be easier to find than causes
Source
Peter Lipton (Inference to the Best Explanation (2nd) [2004], 08 'From cause')
Book Reference
Lipton,Peter: 'Inference to the Best Explanation (2nd ed)' [Routledge 2004], p.137
A Reaction
Presumably the presence of some factor might explain something, but the factor itself might have mysterious causal powers. A catalyst, for example. We don't need to understand the factor that explains.