Full Idea
From a definite cause an effect necessarily follows.
Gist of Idea
From a definite cause an effect necessarily follows
Source
Baruch de Spinoza (The Ethics [1675], I Ax 3)
Book Reference
Spinoza,Benedict de: 'Ethics, Improvement of Understanding, Letters', ed/tr. Elwes,R [Dover 1955], p.46
A Reaction
This encapsulate the view against which Hume was rebelling. However, nowadays no one thinks Spinoza is self-evidently wrong. How are we to distinguish between a cause and a coincident event? We must claim natural necessity.