As Osler stated in his series of lectures on the evolution of medicine, "Sanitation holds its place among the great modern revolutions: political, social and intellectual." With the understanding of the body came new knowledge about the role of bacteria within it. Without modern sanitation techniques, surgeries failed as infection often killed those operated on. Surgeons did not wash their hands before operations, and equipment was rarely disinfected between operations. It took knowing that diseases could come from bacteria and that bacteria could be transmitted from person to person to enable successful medical procedures and increase survival rates around the world