Roald Hoffmann is a Polish-American theoretical chemist who won the Nobel Prize in Chemistry in 1981 for his work on the Woodward-Hoffmann rules, which describe the mechanisms of chemical reactions. He is also a prolific writer of plays and poetry, and a professor of humane letters at Cornell University. Hoffmann was born in 1937 in Poland, where he survived the Holocaust by hiding with his mother and relatives in a schoolhouse. He later immigrated to the United States with his family.