Core formal logic and logical reasoning vocabulary tested on the LSAT, framed as original concept cards.
42 cards · basic cards · AI-written, checked twice. Edit anything.
- What is a conditional statement in logic?
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A statement in the form 'if P, then Q' where P is the antecedent and Q is the consequent.- What is the contrapositive of 'If P, then Q'?
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If not Q, then not P. The contrapositive is logically equivalent to the original conditional.- Is the contrapositive logically equivalent to the original conditional?
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Yes. A statement and its contrapositive are always logically equivalent and have identical truth conditions.- What is the converse of 'If P, then Q'?
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If Q, then P. The converse is NOT logically equivalent to the original.- What is the inverse of 'If P, then Q'?
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If not P, then not Q. The inverse is NOT logically equivalent to the original.- What is a necessary condition?
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A condition that must be true for something else to be true. If P is necessary for Q, then Q cannot occur without P.- What is a sufficient condition?
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A condition that, if true, guarantees something else is true. If P is sufficient for Q, then P guarantees Q.- In 'If P, then Q', which is the necessary condition and which is sufficient?
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P is sufficient for Q; Q is necessary for P.- What is the negation of a statement?
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The opposite truth value. If a statement is true, its negation is false, and vice versa.- What is a disjunction in logic?
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A statement joined by 'or,' true when at least one component is true. In formal logic, this is usually inclusive (or both).- What is a conjunction in logic?
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A statement joined by 'and,' true only when both components are true.- What are De Morgan's Laws?
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Not (P and Q) is equivalent to (not P) or (not Q). Not (P or Q) is equivalent to (not P) and (not Q).- What is logical equivalence?
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Two statements are logically equivalent if they have the same truth value in all possible scenarios.- What is an assumption in logical reasoning?
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An unstated premise that must be true for an argument to work. The argument depends on it even though it is not explicitly stated.- What is a premise in an argument?
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A stated reason or evidence offered to support the conclusion. Premises are the building blocks of an argument.
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