#8 Dr. William Stewart Halsted: Cocaine

William Stewart Halsted was an American surgeon who emphasized strict aseptic technique during surgical procedures, was an early champion of newly discovered anesthetics, and introduced several new operations, including the radical mastectomy for breast cancer.

He often used cocaine as an anesthetic, in the operating room on his patients and out of the operating room on himself.

#9 Stephen Jay Gould: Marijuana

Stephen Jay Gould was an American paleontologist, evolutionary biologist, and historian of science. Gould's most significant contribution to evolutionary biology was the theory of punctuated equilibrium. The theory proposes that most evolution is marked by long periods of evolutionary stability, which is punctuated by rare instances of branching evolution.

He was a medical marijuana user. It was the best way to treat his nausea associated with cancer treatments.

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