Archelaus (philosopher) Archelaus (philosopher) Archelaus (; ; fl. 5th century BCE) was an Ancient Greek philosopher, a pupil of Anaxagoras, and may have been a teacher of Socrates. He asserted that the principle of motion was the separation of hot from cold, from which he endeavoured to explain the formation of the Earth and the creation of animals and humans. Archelaus was a philosopher of the Ionian School, called "Physicus" from having been the first to teach natural philosophy at Athens. This statement of Diogenes Laërtius, is contradicted by Clement of Alexandria, but the two may be reconciled by supposing that Archelaus
Jacob Klein (philosopher) of Plato and the Platonic tradition. As one of many Jewish scholars who were no longer safe in Europe, he fled the Nazis. . The central thesis of his work "Greek Mathematical Thought and the Origin of Algebra" is that the modern concept of mathematics is based on the symbolic interpretation of the Greek concept of number ("arithmos"). Klein died in 1978 in Annapolis, Maryland. Jacob Klein (philosopher) Jacob Klein (March 3, 1899 – July 16, 1978) was a Russian-American philosopher and interpreter of Plato, who worked extensively on the nature and historical origin of modern symbolic mathematics. Klein was