Definizione monolingua

tautology

tautology (countable and uncountable; plural tautologies)

1. (uncountable) redundant use of words

   It is tautology to say, ""Forward Planning"".

2. (countable) An expression that features tautology.

   The expression ""raze to the ground"" is a tautology, since the word ""raze"" includes the notion ""to the ground"".

   • 1946, Bertrand Russell, History of Western Philosophy:

     Pure mathematics consists of tautologies, analogous to ‘men are men’, but usually more complicated.

3. (countable, logic) A statement that is true for all values of its variables

   Given a Boolean A, ""A OR (NOT A)"" is a tautology.

   A logical statement which is neither a tautology nor a contradiction is a contingency.

   A tautology can be verified by constructing a truth tree for its negation: if all of the leaf nodes of such truth tree end in Xs, then the original (pre-negated) formula is a tautology.

Definizione dizionario tautology

	tautologia
	in logic
	expression that features tautology
	A use of redundant language in speech or writing.

tautologia#tautologie logiche

Altri significati:

(uncountable) redundant use of words

(countable) An expression that features tautology.

(countable, logic) A statement that is true for all values of its variables

uncountable: redundant use of words