By definition means true simply because of what the word means. No evidence is needed and none would help.
It is used to close an argument, since saying that something is by definition impossible claims that the question is settled by language rather than by fact. That makes it powerful and occasionally a cheat, because the definition may be exactly what is in dispute. Philosophy calls such statements analytic. In ordinary speech the phrase usually sits after the subject.
1phraseby definitionNecessarily true because of the meaning of the words involved.
“A volunteer is by definition unpaid.”
Practised in A Man Called Ove, Logic & Argument
First appears in chapter 36 of A Man Called Ove.
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