. . . there is no perfect knowledge which can be entitled ours, that is innate; none but what has been obtained from experience, or derived in some way from our senses.
Source: In Peter's Quotations, by Laurence J. Peter, 1977.
-- William Harvey, (Apr 1 1578-1657), English physician; The Father of Modern Physiologydiscovered the true nature of the circulation of the blood and of the function of the heart as a pump.