theory of Forms See PLATO.

theory of frequency See PROBABILITY.

theory of relativity See RELATIVITY.

theory of signs the philosophical and scientific theory of information-carrying entities, communication, and...

theory of types See TYPE THEORY.

theory theory See SIMULATION THEORY.

theosophy any philosophical mysticism, especially those that purport to be mathematically...

Theravada Buddhism See BUDDHISM.

thermodynamics, first law of See ENTROPY.

thermodynamics, second law of See ENTROPY.

thesis See HEGEL.

theurgy See NEOPLATONISM.

thing See METAPHYSICS.

thing-in-itself See KANT.

Third Man argument See PLATO.

thirdness See PEIRCE.

thisness See HAECCEITY.

Thomas Aquinas See AQUINAS.

Thomism the theology and philosophy of Thomas Aquinas. The term is...

Thomson Judith Jarvis (b.1929), American analytic philosopher best known for her...

Thoreau Henry David (1817–62), American naturalist and writer. Born in Concord,...

thought, language of See MEANING, MENTALESE,. PHILOSOPHY OF LANGUAG. thought experiment, a technique...

Thrasymachus (fl. 427 B.C.), Greek Sophist from Bithynia who is known...

Three Profound Treatises See NEO-TAOISM.

three-valued logic See MANY-VALUED LOGIC.

Three Ways See BONAVENTURE.

threshold, absolute See FECHNER.

threshold, relative See FECHNER.

t’i yung, Chinese terms often rendered into English as 'substance' and...

t’ien Chinese term meaning 'heaven', 'sky'. T'ien has a range of...