By the second half of the 18th century universities abandoned Aristotelian natural philosophy and Galenist medicine in favor of the mechanist and vitalist ideas of the moderns, so they placed a greater emphasis on learning by seeing. Everywhere in teaching science and medicine the monotonous diet of dictated lectures was supplemented and sometimes totally replaced by practical courses in experimental physics, astronomy, chemistry, anatomy, botany, "materia medica", even geology and natural history. The new emphasis on practical learning meant that the university now offered a much more welcoming environment to the Republic of Letters. Although most professors and teachers were still uninterested in membership, the ideological and pedagogical changes across the century created the conditions in which the pursuit of curiosity in the university world became much more possible and even attractive.