Proving a negative
Proving a negative or negative proof may refer to: Proving a negative, in the philosophic burden of proof Evidence of absence in general, such as evidence that there is no milk in a certain bowl Modus tollens, a logical proof Proof of impossibility, mathematics Russell's teapot, an analogy: inability to disprove does not prove Sometimes it is mistaken for an argument from ignorance, which is non-proof and a logical fallacy