Robert Kaplan has taught mathematics to people from six to sixty, at leading independent schools and most recently at Harvard University. He is the author of the best-selling The Nothing That Is: A Natural History of Zero, which has been translated into 10 languages, and, with his wife, Ellen, the co-author of The Art of the Infinite.
Ellen Kaplan has taught mathematics to people from six to sixty, at leading independent schools and most recently at Harvard University. With her husband, Robert, she wrote The Art of the Infinite. Ellen is also co-author of Chances Are: Adventures in Probability and Bozo Sapiens: Why to Err is Human, co-written with her son, Michael Kaplan.