Tautology — an expression that repeats in a different verbal form what was previously said. For example: “man is man” or “comprehensive being is unique”.
In traditional logic, tautology is one of the typical logical errors in the definition of a concept.
Tautology in the definition of the concept
This is a logical error that occurs in incorrect definitions of the concept. Its essence lies in the fact that the defined object is defined through itself. For example, a tautology is allowed in the following definition: «an improviser is a person capable of improvising.»
- Demagogy