The aim of this article is a problem of anomalies which occur in experience of delusional patients. This problem is mentioned in cognitive theories of delusions. The author characterizes such theories, but concentrates on bottom-up theories which treat delusion as
a rational answer to anomalous experience. She suggests that they are insufficient for making an explanation of delusions. She tries to emphasize some elements of such theories which can be helpful in explaining and understanding the phenomenon of delusions.