Single Idea 12287

[catalogued under 9. Objects / F. Identity among Objects / 9. Sameness]

Full Idea

If two things are the same then any accident of one must also be an accident of the other, and, if one of them is an accident of something else, so must the other be also. For, if there is any discrepancy on these points, obviously they are not the same.


An 'accident' is a quality it happens to possess

Gist of Idea

Two identical things have the same accidents, they are the same; if the accidents differ, they're different


Aristotle (Topics [c.331 BCE], 152a36)

Book Reference

Aristotle: 'Posterior Analytics and Topica', ed/tr. Tredennick,H/Foster,ES [Harvard 1960], p.653

A Reaction

So what is always called 'Leibniz's Law' should actually be 'Aristotle's Law'! I can't see anything missing from the Aristotle version, but then, since most people think it is pretty obvious, you would expect the great stater of the obvious to get it.