I was surprised that the findings on the brain’s processing of information and discerning of relationships would come as a surprise. I have long been aware of, and have even come to count on, the fact that a surprising degree of insight and clarity often comes in the morning after having fallen asleep the night before wrestling with a complex mathematics or physics problem. I am certain that many, if not most, mathematicians, physicists, and others dealing with difficult problems are equally aware of this phenomenon.

Warren F. Davis
Newton, Mass.

Oliver Sacks, in his book Uncle Tungsten (2001, Knopf), mentions that the arrangement of the elements in the periodic table came to Dmitri Mendeleyev in a dream. Although I certainly do not consider myself in the same league with Mendeleyev, I remember occasionally waking up in the wee hours of the morning with the solution to a computer-programming problem (not always correct) that had been bugging me.

Bill Bornstein
Mount Sinai, N.Y.