Full Idea
He who claims that everything occurs by necessity has no complaint against him who claims that everything does not occur by necessity. For he makes the very claim in question by necessity.
Gist of Idea
If everything is by necessity, then even denials of necessity are by necessity
Source
Epicurus (Principle Doctrines ('Kuriai Doxai') (frags) [c.290 BCE], 40)
Book Reference
Epicurus: 'The Epicurus Reader', ed/tr. Inwood,B. /Gerson,L. [Hackett 1994], p.38