Motivated Reasoning

The tendency to reach the conclusion you already want and then assemble reasons for it — reasoning in service of a predetermined desire rather than toward the truth. Benjamin Franklin gave one of the cleanest illustrations in the literature.

A committed vegetarian, Franklin was tempted by the smell of frying cod. He held out “between principle and inclination” until he noticed that the gutted fish had smaller fish in their stomachs — and concluded, “If you eat one another, I don’t see why we mayn’t eat you.” His own verdict on the episode:

“So convenient a thing to be a reasonable creature, since it enables one to find or make a reason for everything one has a mind to do.”

The Ben Franklin Effect is the same machinery pointed in a useful direction: people rationalize their actions into matching feelings.

Related concepts

• Benjamin Franklin — supplied the canonical illustration: rationalizing his way out of vegetarianism over the smell of frying cod.
• Ben Franklin Effect — the same rationalizing machinery aimed usefully, with people reasoning their actions into matching feelings.
• The Autobiography of Benjamin Franklin — the source for the cod episode and Franklin’s verdict on being a “reasonable creature.”

Where this appears

• The Autobiography of Benjamin Franklin