Full Idea
Do not multiply entities beyond necessity.
Clarification
'entities' are things that exist (so, 'don't be fanciful; keep it simple')
Gist of Idea
Do not multiply entities beyond necessity
Source
William of Ockham (works [1335])
A Reaction
This is the classic statement of Ockham's Razor, though it is not found in his printed works. It appears to be mainly aimed at Plato's Theory of Forms. It is taken to refer to types of entities, not numbers. One seraph is as bad as a hundred.
Related Idea
Idea 16676 Why use more things when fewer will do? [William of Ockham]