Congruence Bias

Congruence Bias is the tendency to test a hypothesis exclusively by searching for evidence that confirms it, rather than by attempting to falsify it or testing alternative hypotheses. When you have an initial theory about why something is happening, the bias drives you to gather only data that could prove you right — never data that could prove you wrong. A founder who believes their product is losing customers due to pricing will survey customers about price sensitivity, but never test whether the real issue is onboarding friction. An investor convinced a company will succeed will research the bull case exhaustively while spending zero time on the bear case. Congruence Bias is distinct from confirmation bias: it's not about interpreting evidence favourably, it's about never generating the disconfirming evidence in the first place.

For every hypothesis you're testing, explicitly generate at least one alternative explanation and design a test that could distinguish between them. Instead of asking "Is A true?" ask "Is A or B a better explanation?" Force yourself to spend equal time on the bull and bear case. Use pre-registration: write down what evidence would change your mind before you start gathering evidence. If your test can only confirm your hypothesis — never disconfirm it — the test is worthless.

Congruence Bias drives you to test only your preferred hypothesis and never generate disconfirming evidence. In business, it leads to validation theatre — experiments designed to confirm rather than genuinely test. The antidote is explicitly generating alternative hypotheses and designing tests that can distinguish between them.