The chemist August Kekulé was thinking of how benzene arranged its six carbon and hydrogen atoms. Thinking in regards to the problem, he dozed off, and dreamt of dancing atoms that fell right into a snakelike sample, which led him to find out the benzene ring. As Kekulé wrote in https://charlieqmdtj.bloggazza.com/28162607/not-known-details-about-problem-solving