Flashes of Intuition and Scientific Revolutions

In the chapter “Revolutions as Changes of World View,” of The Structure of Scientific Revolutions, Kuhn discusses whether theories “simply [are] man-made interpretations of given data.” And he mentions something that interests me, namely the role of intuition in the process of discovery:

Paradigms are not corrigible by normal science at all. Instead, as we have already seen, normal science ultimately leads only to the recognition of anomalies and to crises. And these are terminated, not by deliberation and interpretation, but by a relatively sudden and unstructured event like the gestalt switch [emphasis mine]. Scientists then often speak of the “scales falling from the eyes” or of the “lightning flash” that “inundates” a previously obscure puzzle, enabling its components to be seen in a new way that for the first time permits its solution. On other occasions the relevant illumination comes in sleep. No ordinary sense of the term “interpretation” fits these flashes of intuition through which a new paradigm is born. Though such intuitions depend upon the experience, both anomalous and congruent, gained with the old paradigm, they are not logically or piecemeal linked to particular items of that experience as an interpretation would be. Instead, they gather up large portions of that experience and transform them to the rather different bundle of experience that will thereafter be linked piecemeal to the new paradigm but not to the old.

Henri Poincaré is also famous for a sudden flash of insight, and of course there’s Archimedes’s “Eureka!” and Newton’s apple. And I thought that the discovery of the double-helix structure of DNA came as a flash to James Watson while gazing into a fire, but that’s wrong. According to his The Double Helix: A Personal Account of the Discovery of the Structure of DNA, he had made cardboard cutouts of the nucleotides, which he shifted around to find out how they linked together:

When I got to our still empty office the following morning, I quickly cleared away the papers from my desk top so that I would have a large, flat surface on which to form pairs of bases held together by hydrogen bonds. Though I initially went back to my like-with-like prejudices, I saw all to well that they led nowhere. When Jerry [Donohue, a crystallographer] came in I looked up, saw that it was not Francis [Crick, his partner], and began shifting the bases in and out of various other pairing possibilities. Suddenly I became aware that an adenini-thymine pair held together by two hydrogen bonds was identical in shape to a guanine-cytosine pair held together by at least two hydrogen bonds. All the hydrogen bonds seemed to form naturally; no fudging was required to make the two types of base pairs identical in shape.