“A chemist colleague of mine runs a seminar in which art and science are brought together. And one such session was devoted to olfaction. And there was an olfactory physiologist from Columbia and a friend of his, a parfumier. Forgive my French accent. And the parfumier had made something unlike anything ever encountered on earth. And it had a very strong smell which aroused no associations and could not be compared to anything. One realized this was absolute novelty.” The Rumpus interviews Oliver Sacks about his new book, Hallucinations.