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Belief Bias

Belief Bias


Belief Bias is a tendency to assess the strength of an argument on the basis of how well the conclusion fits with our system of beliefs. This means that people often accept an argument because the conclusion is consistent with their beliefs without even considering the logic of the statement. People will tend to reject arguments that are outside of their belief systems, even though the assertion may be logical and feasible. The bias is especially noticeable with people who have experienced limited educational opportunities.


The Russian neuropsychologist Alexander Luria conducted research (1976) among illiterate farmers in Central Asia to evaluate their powers of deduction. He used statements like “There are no camels in Germany; the city of B is in German; are there camels there or not?” The kind of response he got was “I don’t know, I have never seen German villages. If it is a large city, there should be camels there.” He asked a further question; “But what if there aren’t any in all of Germany? Answer; “If B is a village, there is probably no room for camels.”


Avoid using pure logic to persuade people when you outline the benefits of something that is outside of their beliefs. You are most likely to succeed if you focus on how it solves a concrete problem for them and keep within their existing belief system. People buy benefits and solutions, not features.


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