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Germ Theory
The germ theory, which emerged in the late 19th century, demonstrated that microscopic germs caused most human infectious diseases. The germs involved included bacteria, viruses, fungi, protozoa, and prions. Louis Pasteur (1822-1895), a French...
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How We Discovered Germs
Humanity didn't always know about the invisible viruses, bacteria, and microbes that can cause disease. But that doesn't mean we didn't come up with some truly bizarre ideas. From the four humors and miasma theory to bloodletting and trepanation...
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Pasteurization Experiment
Louis Pasteur's pasteurization experiment illustrates the fact that the spoilage of liquid was caused by particles in the air rather than the liquid itself. These experiments were important pieces of evidence supporting the idea of Germ Theory...
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Louis Pasteur
Restored studio portrait of Louis Pasteur (1822-1895), photographed by Paul Nadar.
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Robert Koch
Portrait of Robert Koch (1843-1910), published in 1907 in Les Prix Nobel.
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Cholera Bacterium
Scanning electron microscope image of Vibrio cholerae. This is the bacterium that causes cholera.
Definition
George Berkeley
George Berkeley (1685-1753) was an Anglo-Irish bishop and an empiricist and idealist philosopher. He infamously claimed that no matter exists outside of God and that things only exist outside of our minds and perceptions because God perceives...
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How a Few Scientists Transformed the Way We Think about Disease - Tien Nguyen
View full lesson: http://ed.ted.com/lessons/how-a-few-scientists-transformed-the-way-we-think-about-disease-tien-nguyen This video was created with support from the U.S. Office of Research Integrity: http://ori.hhs.gov. For several...
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The Theory of Omens
On this clay tablet, the author has listed the titles of cuneiform omen collections drawn from celestial and terrestrial phenomena. Rather unusually, he explains that the validity of an individual omen depends on the particular month and...
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One of History's Most Dangerous Myths - Anneliese Mehnert
Examine the empty land theory, which was created by European colonizers in South Africa to support their claims to the region. From the 1650s through the late 1800s, European colonists descended on South Africa. They sought to claim the...