The purpose of the scientific endeavour is to discover the order in the natural world, to discover general principles on the basis of which we can rationally understand, perhaps predict and maybe even control naturalistic phenomena. In this context the phenomenon of delusional thinking, like that of creativity, presents a tremendous challenge as delusions, like novel ideas and dreams, have a certain erratic, ficklequality whichqualifies them, for some people, as deserving of the title 'irrational'. Hermann Lenz, for example (personal communication, 26 October 1987), did not believe that my experimental study was even appropriate in the first instance as he takes the view that delusions are of this irrational ilk and thus not amenable to scientific enquiry. Hausman (1976, 1985) similarly argues that creativity by its very nature involves breaking boundaries in unpredictable ways and hence the quest to predetermine creative behaviour suffers from a logical contradiction at the very outset.