Impossibility may refer to:
Philosophy and logic[edit]
- Epistemic impossibility, in modal logic a statement that cannot be true, given what we know
- Subjunctive impossibility, types of statement that cannot be true based on various types of subjunctive modality
- Logical impossibility, a statement that contains a logical contradiction
- Impossible world, a concept in philosophical logic
Other uses[edit]
- Impossibility of performance, in contract law an excuse for non-performance of a contract
- Impossibility defense, a criminal defense for a crime that was legally impossible to commit
- Proof of impossibility, in mathematics a proof that demonstrates that a particular problem cannot be solved