History
Psoralens have been known since ancient Egypt but have only been available in a chemically synthesized form since the 1970s.
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Famous quotes containing the word history:
“Classes struggle, some classes triumph, others are eliminated. Such is history; such is the history of civilization for thousands of years.”
—Mao Zedong (1893–1976)
“A man will not need to study history to find out what is best for his own culture.”
—Henry David Thoreau (1817–1862)
“There has never been in history another such culture as the Western civilization M a culture which has practiced the belief that the physical and social environment of man is subject to rational manipulation and that history is subject to the will and action of man; whereas central to the traditional cultures of the rivals of Western civilization, those of Africa and Asia, is a belief that it is environment that dominates man.”
—Ishmael Reed (b. 1938)