Full Idea
There must be at least as much in the cause as there is in the effect.
Gist of Idea
There must be at least as much in the cause as there is in the effect
Source
René Descartes (Meditations [1641], §3.49)
Book Reference
Descartes,René: 'Discourse on Method/The Meditations', ed/tr. Sutcliffe,F.E. [Penguin 1968], p.128