Madness Explained: Psychosis and Human Nature

by Richard P. Bentall

(The philosopher of science Sir Karl Popper argued that data that refute a hypothesis are nearly always more informative than data that appear to support it.43 This is because negative evidence can be decisive whereas positive evidence may support several alternative hypotheses. Popper therefore suggested that scientists should vigorously seek evidence that disconfirms their pet theories in the hope that there will be no such evidence. Ordinary people, however, usually seek evidence that favours their ideas, a phenomenon known to psychologists as the confirmation bias.44 Interestingly, some studies have shown this bias in professional scientists, although whether it has an adverse affect on their work remains a matter of debate.)