Across
- 2. - At least one is true
- 4. – Always true proposition.
- 6. - Represents a statement that is always false.
- 9. – Symbol for the set of integers.
- 13. - Both are true
- 14. - Represents a statement that is always true.
Down
- 1. - If the first is true, then the second is true. NATURALS – Symbol for the set of natural numbers.
- 3. – Set of elements common to two sets.
- 5. – Semantic entailment; a formula logically follows from another.
- 7. - It is not the case that
- 8. – Another notation for logical implication.
- 10. - Used to denote a conclusion derived from premises.
- 11. - Denotes syntactic entailment; indicates that a statement can be derived from a set of axioms.
- 12. – Set of elements belonging to at least one of two sets