Leibniz Invents the Integral Symbol: Calculus Gets Its Look
Leibniz needed a symbol for summation in his new calculus. He chose the long s—basically an elongated letter that looked like ∫. It stood for "summa." Newton had developed calculus independently using different notation. Leibniz published first. His symbols won. Every integral you've ever seen uses the mark he picked on this day.
October 29, 1675
351 years ago
Key Figures & Places
What Else Happened on October 29
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Tropas bizantinas ocupam Antioquia, na Síria.
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