Argumentum ad baculum (Latin: argument to the cudgel or appeal to the stick), also known as appeal to force, is said by some to be a logical fallacy. It is where force, or the threat of force, is given as an argument for a conclusion.

One participates in argumentum ad baculum when one points out the negative consequences of holding the contrary position. For example, many young people in the United States who opposed the Vietnam War were told that they should not hold such a view, because they would face discrimination from potential employers.

A similar fallacy is the claim that one should believe in the validity of the Bible lest God strike you down!

Since the Middle Ages, this form of argument has been identified as a logical fallacy by many philosophers, but pragmatists and others claim not only that it is no fallacy, but rather that many of our beliefs are based on this kind of useful reasoning.

The argumentum ad baculum is a special case of argumentum ad consequentiam, or "appeal to consequences".