An embroidered patch made with a durable twill weave
featuring the formal symbolism for the law of non-contradiction in propositional logic.
The formula reads as "not both P and not-P". It is a foundational axiom in classical logic that, for any proposition, P, it cannot be the case that both P and not-P.
- Black patch with gold formula and border in threaded embroidery
- 3″ (7.6 cm) in diameter
- 26% cotton, 74% polyester
- Attachment options: iron-on, sew-on, or safety pin