torek, 17. marec 2026

Isaac Newton stuck a needle in his own eye as part of an experiment.

Famous Figures

I f you're brave enough, there is no more convenient scientific subject than your own body: You're intimately familiar with it, you get near-instant feedback, and you always have it with you (though, to be clear, we are not suggesting you do this at home). Some of history's most famous inventors have used themselves as guinea pigs, and in some pretty shocking ways.

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By the Numbers

Listing price of Isaac Newton's personal copy of Opticks

$467,000

Width (in millimeters) of one side of the world's smallest recorded prism

0.01

Did you know?

Isaac Newton was really into alchemy.

Newton is remembered as a man of science, but he certainly dabbled in more esoteric pursuits, too. A trove of his papers sold at auction in 1936 revealed thousands of pages devoted to alchemy, the pseudoscientific study of the transmutation of matter that flourished in the Middle Ages. Newton's notes included work on finding the philosopher's stone, a magical substance said to perform miracles such as turning lead into gold and creating an elixir of life. Even at the time, alchemy was considered radical, and Newton's alchemy manuscripts were deemed not fit to be printed upon his death.