Truth Values and Tautologies
Considering different interpretations of the same statement leads to the notion of truth value. Simplest approach to truth values means that the statement may be "true" in one case, but "false" in another. In one sense of the term "tautology", it is any type of formula or proposition which turns out to be true under any possible interpretation of its terms (may also be called a valuation or assignment depending upon the context). This is synonymous to logical truth.
However, the term "tautology" is also commonly used to refer to what could more specifically called truth-functional tautologies. Whereas a tautology or logical truth is true solely because of the logical terms it contains in general (e.g. "every", "some", and "is"), a truth-functional tautology is true because of the logical terms it contains which are logical connectives (e.g. "or", "and", and "nor"). Not all logical truths are tautologies of such kind.
Read more about this topic: Logical Truth
Famous quotes containing the words truth, values and/or tautologies:
“The tension to mother the “right” way can leave a peculiar silence within mother daughter relationships—the silence of a mother’s own truth and experience. Within this silence, a daughter’s authentic voice can also fall silent. This is the silence of perfection. This silence of perfection prevents mothers from listening and learning from their daughters.”
—Elizabeth Debold (20th century)
“Our first line of defense in raising children with values is modeling good behavior ourselves. This is critical. How will our kids learn tolerance for others if our hearts are filled with hate? Learn compassion if we are indifferent? Perceive academics as important if soccer practice is a higher priority than homework?”
—Fred G. Gosman (20th century)
“Propositions show what they say: tautologies and contradictions show that they say nothing.”
—Ludwig Wittgenstein (1889–1951)