Bulverism

Bulverism is a logical fallacy that combines a genetic fallacy with circular reasoning. The method of Bulverism is to "assume that your opponent is wrong, and explain his error". The Bulverist assumes a speaker's argument is invalid or false and then explains why the speaker came to make that mistake, attacking the speaker or the speaker's motive. The term "Bulverism" was coined by C. S. Lewis to poke fun at a very serious error in thinking that, he alleges, recurs often in a variety of religious, political, and philosophical debates.

Similar to Antony Flew's "Subject/Motive Shift", Bulverism is a fallacy of irrelevance. One accuses an argument of being wrong on the basis of the arguer's identity or motive, but these are strictly speaking irrelevant to the argument's validity or truth. But it is also a fallacy of circular reasoning, since it assumes, rather than argues, that one's opponent is wrong.

Lewis wrote about this in a 1941 essay which was later expanded and published in The Socratic Digest under the title "Bulverism". This was reprinted both in Undeceptions and the more recent anthology God in the Dock. He explains the origin of this term:

You must show that a man is wrong before you start explaining why he is wrong. The modern method is to assume without discussion that he is wrong and then distract his attention from this (the only real issue) by busily explaining how he became so silly.

In the course of the last fifteen years I have found this vice so common that I have had to invent a name for it. I call it "Bulverism". Some day I am going to write the biography of its imaginary inventor, Ezekiel Bulver, whose destiny was determined at the age of five when he heard his mother say to his father — who had been maintaining that two sides of a triangle were together greater than a third — "Oh you say that because you are a man." "At that moment", E. Bulver assures us, "there flashed across my opening mind the great truth that refutation is no necessary part of argument. Assume that your opponent is wrong, and explain his error, and the world will be at your feet. Attempt to prove that he is wrong or (worse still) try to find out whether he is wrong or right, and the national dynamism of our age will thrust you to the wall." That is how Bulver became one of the makers of the Twentieth Century.

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