Okuzeka
Philosophy vocabulary · Logic and Argument

Tautology

Meaning in philosophy, with examples

/tɔːˈtɒlədʒi/nounAdvanced term

In philosophy, tautology means: In logic, a statement that is true in every possible case because of its form alone, such as 'Either it is raining or it is not raining'.

In Turkish: totoloji, genel geçer önerme

How it is used

Checked with truth tables in propositional logic. In everyday English and rhetoric, a tautology is a needless repetition (a free gift) or an empty statement, and calling a claim tautological often means it says nothing informative.

Example sentences

  1. 'P or not P' is a tautology: no assignment of truth values can make it false.

  2. Critics say 'survival of the fittest' becomes a tautology if the fittest simply means those who survive.

Common collocations

  • logical tautology
  • a mere tautology
  • tautological statement
  • truth table
  • contradictionA statement, or a pair of statements, that cannot possibly be true, such as claiming both that something is the case and that it is not.
  • truthThe property a statement or belief has when it matches how things are; philosophers disagree about what this matching really consists in.
  • logicThe study of correct reasoning, especially of which conclusions follow from which premises and why.
  • validDescribes an argument whose form guarantees that if all the premises are true, the conclusion must be true as well.

More terms: Logic and Argument

Practise with graded reading

Reading at the right level is the fastest way to make new words stick. Pick free English books by level: