self-evident truth
Noun
Meaning
an assumption that is basic to an argument
Source: WordNetSynonyms
Hypernyms
Examples
We unite behind a declaration of self-evident truth.
In general, a non-logical axiom is not a self-evident truth, but rather a formal logical expression used in deduction to build a mathematical theory.
In formal systems, the word axiom has a special meaning, different from the ordinary meaning of "a self-evident truth".