All goes on as if the inventor were an examiner for the second degree who would only have to question the candidates who had passed a previous examination. Never in the field of his consciousness do combinations appear that are not really useful, except some that he rejects but which have to some extent the characteristics of useful combinations. The sterile combinations do not even present themselves to the mind of the inventor. Here the samples would be so numerous that a whole lifetime would not suffice to examine them. It makes one think of a purchaser before whom are displayed a large number of samples, and who examines them, one after the other, to make a choice.
To invent, I have said, is to choose but the word is perhaps not wholly exact. Among the countless fascinating books it references is The Foundations of Science ( public library), originally published in 1908 by the legendary French mathematician, philosopher of science, and polymath Henri Poincaré (1854-1912), who offers the following account of ideation and the creative process, emphasizing both the combinatorial nature of creativity and the importance of editing and subtraction:
One such particularly prolific treasure trove of pointer to related works is the 1957 gem The Art of Scientific Investigation, which you might recall from recent looks at its insights on serendipity and chance-opportunism and the role of intuition in discovery and creation. Great books are always Rube Goldberg machines of discovery for other great books, with their intricately woven mesh of allusions, references, and citations.