As a consequence, scientists who are carefully reflectiveabout their activity do not instinctively ask the question ‘Is itreasonable?’ as if they were confident beforehand what shaperationality had to take. We have noted how ‘unreasonable’, inclassical Newtonian terms, the nature of light turned out tobe. Instead, for the scientist the proper phrasing of the truth-seeking question takes the form, ‘What makes you think thatmight be the case?