LOUIS PASTEUR AND JOSEPH LISTER
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LOUIS PASTEUR
The prevailing theory of his time was "spontaneous generation," a belief that living organisms sprang to life from decaying organic matter. Scientists had previously discarded the idea that larger animals came into being this way (mice from dirty hay, or maggots from decaying meat). But, most scientists still believed that microscopic organisms were the result of spontaneous generation. It was Pasteur who proved them wrong, utilizing a well-designed experiment. Working in the high Alps, he used an ingenious method of filtering the air to prove decomposing food produces no new organisms - new organisms only occur when they're introduced from the outside, through non-filtered air. This germ theory became the foundation upon which hygienic principles of medical care were based.
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JOSEPH LISTER
In Lister's time, there were two prevailing theories of disease the surgeons clung to, neither of which pointed to them having any involvement in the spread of infections. The first was "miasma," the belief that disease was carried about by noxious gases floating in the air. Their second theory was that the infections in the patient's wounds occurred spontaneously, being generated by some unknown, and unavoidable, action within the flesh itself. Both theories meant the surgeons had no responsibility in causing their patient's infections - and the death tolls continued to rise, Lister had other ideas.
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