Appeal to motive

Appeal to motive is a pattern of argument which consists in challenging a thesis by calling into question the motives of its proposer. It can be considered as a special case of the ad hominem circumstantial argument. As such, this type of argument is an informal fallacy.

A common feature of appeals to motive is that only the possibility of a motive (however small) is shown, without showing the motive actually existed or, if the motive did exist, that the motive played a role in forming the argument and its conclusion. Indeed, it is often assumed that the mere possibility of motive is evidence enough.