Willed ignorance

I've got my mind made up, so don't confuse me with the facts. This is usually a case of the Traditional Wisdom Fallacy.

Example:

Of course she's made a mistake. We've always had meat and potatoes for dinner, and our ancestors have always had meat and potatoes for dinner, and so nobody knows what they're talking about when they start saying meat and potatoes are bad for us.

Traditional Wisdom

If you say or imply that a practice must be OK today simply because it has been the apparently wise practice in the past, you commit the fallacy of traditional wisdom. Procedures that are being practiced and that have a tradition of being practiced might or might not be able to be given a good justification, but merely saying that they have been practiced in the past is not always good enough, in which case the fallacy is committed. Also called argumentum consensus gentium when the traditional wisdom is that of nations.

Example:

Of course we should buy IBM's computer whenever we need new computers. We have been buying IBM as far back as anyone can remember.

The "of course" is the problem. The traditional wisdom of IBM being the right buy is some reason to buy IBM next time, but it's not a good enough reason in a climate of changing products, so the "of course" indicates that the fallacy of traditional wisdom has occurred.

Past Practice

See Traditional Wisdom.

Consensus Gentium

Fallacy of argumentum consensus gentium (argument from the consensus of the nations). See Traditional Wisdom.

Common Practice

See Appeal to the People and Traditional Wisdom.

Common Belief

See Appeal to the People and Traditional Wisdom.