Full Idea
Nothing exists from whose nature an effect does not follow.
Gist of Idea
All natures of things produce some effect
Source
Baruch de Spinoza (The Ethics [1675], I Pr 36)
Book Reference
Spinoza,Benedict de: 'Ethics', ed/tr. White,WH/Stirling,AH [Wordsworth 2001], p.34
A Reaction
I take it that this is because it is analytic that essences produce effects, since that is the point of the concept of an essence - as the source of the explanations of the effects.