The fallacy known as the ‘allegation of the neglected onus’ occurs when an individual charges that his opponent’s position does not sufficiently deal with an obligation that has not been shown to properly belong to the opponent’s position. It can also be called the charge of neglected incumbency. As such, it constitutes an illegitimate attempt to discredit a position by asserting a charge that such a position does not sufficiently deal with an issue that does not legitimately belong to it. Inasmuch as this fallacy entails a mischaracterization of one’s position, it resembles the straw man fallacy detailed below.
For example, a ‘creation scientist’ might assert that ‘evolutionary theories’ offer man nothing to resolve the problem of universals – the so-called ‘problem of the one and the many’ which has eluded many philosophers and schools of thought, thus implying that advocacy of ‘evolutionary theories’ amounts to the advocacy of failure in this regard. Obviously the statement to the effect that ‘evolutionary theories’ do nothing to resolve the problem of universals can be said to be true, however this does not constitute a failing on the part of evolutionary theories. The task of evolutionary theories (in biology) is of narrow scientific scope; their task is not to deal with problems of epistemology. An individual imputing evolutionary theories with this failure or negligence improperly imparts an essential epistemological task to a set of scientific theories. By its very nature as a study of specific scientific scope, evolution is not intended to offer man epistemological solutions, and to hold it to such obligations is indeed highly suspicious.
In some ways, allegation of the neglected onus resembles other common fallacies of relevance, specifically missing the point and straw man fallacies. This fallacy is akin to missing the point (ignoratio elenchi) for it often fails to take into account the fact the essential nature of a position (e.g., evolution or evolutionary theories) does not logically apply to the conclusion the arguer is trying to draw (i.e., failure of epistemological tasks). This fallacy also can resemble a straw man argument for it essentially entails a mischaracterization of the subject matter in question (e.g., evolution). Evolutionary theories are no more suited to handle epistemological issues than aerodynamic principles or geological theories.