In 1936, at the Philosophy Department of the City College of New York (CCNY), he studied Aristotle with Abraham Edel, Leibniz with Philipp P. Wiener, and mathematical logic and linguistics with Alfred Tarski.
During this time, he developed an interpretation of human evolution which resulted in him leaving his focus on philosophy and commencing an intensive study of the Eurasian nomads; becoming a fellow of the Far Eastern Institute at the University of Washington in Seattle.
In 1952, Krader taught linguistics as a Fellow of the Russian Research Center at Harvard and married his wife Dr. Barbara Lattimer in 1953.
In 1954 he graduated at Harvard with a PhD on "Kinship Systems of the Altaic-speaking peoples of the Asian Steppes" (supervised by Clyde Kluckhohn).
From 1989 until his death, Krader produced 156 manuscripts including works on Labour and Value: a Theory of the Russian Revolution, Mathematical Logic, a Critique of Evolution, Linguistics and other topics.