enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Necessity and sufficiency - Wikipedia

    en.wikipedia.org/wiki/Necessity_and_sufficiency

    In logic and mathematics, necessity and sufficiency are terms used to describe a conditional or implicational relationship between two statements. For example, in the conditional statement: "If P then Q ", Q is necessary for P, because the truth of Q is guaranteed by the truth of P. (Equivalently, it is impossible to have P without Q, or the ...

  3. If and only if - Wikipedia

    en.wikipedia.org/wiki/If_and_only_if

    In logic and related fields such as mathematics and philosophy, " if and only if " (often shortened as " iff ") is paraphrased by the biconditional, a logical connective [1] between statements. The biconditional is true in two cases, where either both statements are true or both are false. The connective is biconditional (a statement of ...

  4. Conditional statement - Wikipedia

    en.wikipedia.org/wiki/Conditional_statement

    A conditional statement may refer to: A conditional formula in logic and mathematics, which can be interpreted as: Material conditional. Strict conditional. Variably strict conditional. Relevance conditional. A conditional sentence in natural language, including: Indicative conditional. Counterfactual conditional.

  5. Material conditional - Wikipedia

    en.wikipedia.org/wiki/Material_conditional

    Mathematical logic. Philosophy of logic. Category. v. t. e. The material conditional (also known as material implication) is an operation commonly used in logic. When the conditional symbol is interpreted as material implication, a formula is true unless is true and is false.

  6. Contraposition - Wikipedia

    en.wikipedia.org/wiki/Contraposition

    Contraposition. In logic and mathematics, contraposition, or transposition, refers to the inference of going from a conditional statement into its logically equivalent contrapositive, and an associated proof method known as § Proof by contrapositive. The contrapositive of a statement has its antecedent and consequent inverted and flipped.

  7. List of logic symbols - Wikipedia

    en.wikipedia.org/wiki/List_of_logic_symbols

    propositional logic, Boolean algebra, first-order logic. ⊥ {\displaystyle \bot } denotes a proposition that is always false. The symbol ⊥ may also refer to perpendicular lines. The proposition. ⊥ ∧ P {\displaystyle \bot \wedge P} is always false since at least one of the two is unconditionally false. ∀.

  8. Conditional sentence - Wikipedia

    en.wikipedia.org/wiki/Conditional_sentence

    Conditional sentences are natural language sentences that express that one thing is contingent on something else, e.g. "If it rains, the picnic will be cancelled." They are so called because the impact of the main clause of the sentence is conditional on the dependent clause. A full conditional thus contains two clauses: a dependent clause ...

  9. Logical biconditional - Wikipedia

    en.wikipedia.org/wiki/Logical_biconditional

    In logic and mathematics, the logical biconditional, also known as material biconditional or equivalence or biimplication or bientailment, is the logical connective used to conjoin two statements and to form the statement " if and only if " (often abbreviated as " iff " [1]), where is known as the antecedent, and the consequent. [2][3] Nowadays ...