Isaac Barrow (1630-1677), English mathematician, who resigned his post at Cambridge University, England, in favor of his pupil Isaac Newton. Barrow graduated in 1648 but because of unrest during Cromwell's rule was unable to take up an academic post until 1660, when he became Professor of Greek at Cambridge University. From 1664 to 1669 he held the Lucasian Chair in Mathematics, inherited by Newton at age 27. Barrow came close to anticipating some of the concepts of differential calculus that Newton later expounded. He was a noted classicist and theologian.