Susanne Katherina Langer was an American philosopher, writer, and educator known for her theories on the influences of art on the mind. She was one of the earliest American women to achieve an academic career in philosophy and the first woman to be professionally recognized as an American philosopher. Langer is best remembered for her 1942 book Philosophy in a New Key, which was followed by a sequel, Feeling and Form: A Theory of Art, in 1953. In 1960, Langer was elected a Fellow of the American Academy of Arts and Sciences.

William Leonard Langer was an American historian, intelligence analyst and policy advisor. He served as chairman of the history department at Harvard University. He was on leave during World War II as head of the Research and Analysis Branch of the Office of Strategic Services. He was a specialist on the diplomacy of the periods 1840–1900 and World War II. He edited many books, including a series on European history, a large-scale reference book, and a university textbook.