Full Idea
A cause may be a cause either in its own right or coincidentally. The cause in its own right of a house is house-building ability, but a house may coincidentally be caused by something pale or educated. ..There could be infinite coincidental causes.
Gist of Idea
Causes produce a few things in their own right, and innumerable things coincidentally
Source
Aristotle (Physics [c.337 BCE], 196b25)
Book Reference
Aristotle: 'Physics', ed/tr. Waterfield,Robin [OUP 1996], p.44
A Reaction
If we seriously want to identify THE cause of an event, this distinction seems useful, even though a cause 'in its own right' is a rather loose locution. It leads on to analyses of necessary and sufficient conditions.