Appeal to Common Practice


Also called It-Ought Fallacy.




The basic idea behind the fallacy is that the fact that most people do a is used as "evidence" to support the action or practice. It is a fallacy because the mere fact that most people do something does not make it correct, moral, justified, or reasonable:

This argument rests heavily on the principle of relevant difference. On this principle two people, p1 and p2, can only be treated differently if and only if there is a relevant difference between them. For example, it would be fine for me to give a better grade to p1 than p2 if p1 did better work than p2. However, it would be wrong of me to give p1 a better grade than p2 simply because p1 has red hair and p2 has blonde hair. An appeal to fair play, which might seem to be an appeal to common practice, need not be a fallacy.

There might be some cases in which the fact that most people accept a as moral entails that a is moral (cultural relativism). For example, one view of morality is that morality is relative to the practices of a culture, time, person, etc. If what is moral is determined by what is commonly practiced, then this argument:







