"Science is a river with two sources, the practical source and the theoretical source." ― Alfred North Whitehead From Alfred North Whitehead Philosopher Added on 1/31/2026 About Alfred North Whitehead Alfred North Whitehead was an English mathematician and philosopher known for co-authoring Principia Mathematica and for developing process philosophy. He later taught at Harvard University. He died in 1947. Born: 1861-02-15 Died: 1947-12-30 View all quotes from Alfred North Whitehead