Argument from ignorance

The argumentum ad ignorantiam ( Latin for " argument that appeals to the non-knowledge ") is a logical fallacy in which a thesis is declared to be wrong, if only because it could not be proven wrong, or vice versa, a thesis is declared properly if only because it has not yet been disproved. The fallacy is pulled without factual arguments. The so Argumentierende sees his lack of imagination or his ignorance as sufficient for the refutation or confirmation of a thesis.

A variation of this is the " argument from personal incredulity ": The fact that a thesis subjectively appears to be unbelievable or unlikely, is regarded as a sufficient condition for the rejection of a thesis in place of another, subjectively preferred is set as true.

Both arguments usually the following scheme together: A person considered the lack of evidence for a claim - or, alternatively, looking at her personal bias against this view - as causative evidence or proof that a different claim is true. This is not a valid final way in the sense of formal logic.

The argument from ignorance, or the argument from personal incredulity should not be confused with the reductio ad absurdum, which is a valid method in which a logical contradiction is used in order to refute a thesis.