There Is No Such Thing as Unconscious Thought

The great French mathematician and physicist Henri Poincaré (1854–1912) took a particular interest in the origins of his own astonishing creativity. His achievements were impressive: His work profoundly reshaped mathematics and physics—including laying crucial foundations for Einstein’s theory of relativity and the modern mathematical analysis of chaos. But he also had some influential speculations about where many of his brilliant ideas came from: unconscious thought.

Poincaré found that he would often struggle unsuccessfully with some mathematical problem, perhaps over days or weeks (to be fair, the problems he got stuck on were difficult, to say the least). Then, while not actually working on the problem at all, a possible solution would pop into his mind. And when he later checked carefully, the solution would almost always turn out to be correct.

How was this possible? Poincaré’s own suspicion was that his unconscious mind was churning through possible approaches to the problem “in the background”—and when an approach seemed aesthetically “right,” it might burst through into consciousness. Poincaré believed that this “unconscious thought” process was carried out by what might almost be a second self, prepared and energized by periods of conscious work, yet able to work away on the problem in hand entirely below the level of conscious awareness.

Why do solutions to problems suddenly pop into our minds?

The notable 20th-century German composer Paul Hindemith, in his book A Composer’s World, reports a similar belief, with a striking metaphor. “We all know the impression of a very heavy flash of lightning in the night. Within a second’s time we see a broad landscape, not only in its general outlines but with every detail,” Hindemith writes. “If we cannot, in the flash of a single moment, see a composition in its absolute entirety, with every pertinent detail in its proper place, we are not genuine creators.”

Taken literally, Hindemith’s claim would seem