Bortolotti L. (2018) Delusions and Three Myths of Irrational Belief.
In: Bortolotti L. (eds) Delusions in Context. Palgrave Macmillan, Cham
This chapter addresses the contribution that the delusion literature has made to the philosophy of belief. Three conclusions will be drawn: (1) a belief does not need to be epistemically rational to be used in the interpretation of behaviour; (2) a belief does not need to be epistemically rational to have significant psychological or epistemic benefits; (3) beliefs exhibiting the features of epistemic irrationality exemplified by delusions are not infrequent, and they are not an exception in a largely rational belief system. What we learn from the delusion literature is that there are complex relationships between rationality and interpretation, rationality and success, and rationality and knowledge.
The chapter is here.
Here is a portion of the Conclusion:
Second, it is not obvious that epistemically irrational beliefs should be corrected, challenged, or regarded as a glitch in an otherwise rational belief system. The whole attitude towards such beliefs should change. We all have many epistemically irrational beliefs, and they are not always a sign that we lack credibility or we are mentally unwell. Rather, they are predictable features of human cognition (Puddifoot and Bortolotti, 2018). We are not unbiased in the way we weigh up evidence and we tend to be conservative once we have adopted a belief, making it hard for new contrary evidence to unsettle our existing convictions. Some delusions are just a vivid illustration of a general tendency that is widely shared and hard to counteract. Delusions, just like more common epistemically irrational beliefs, may be a significant obstacle to the achievements of our goals and may cause a rift between our way of seeing the world and other people’s way. That is why it is important to develop a critical attitude towards their content.