Polish science reached its culmination in the first half of the 16th century as the medieval point of view was criticized and more rational explanations were sought. "De revolutionibus orbium coelestium", published by Copernicus in Nuremberg in 1543, shook up the traditional value system extended into understanding of the physical universe, dispensing with the Christianity-adopted Ptolemaic anthropocentric model and setting free the expansion of scientific inquiry. Generally the prominent scientists of the period resided in many different regions of the country, and increasingly, the majority were of urban, rather than noble origin.