The 'Leibniz' Series for Pi Was Written in a Kerala Verse Two Centuries Before Leibniz. Was It Calculus? Here Is What the Palm Leaves Prove

Calicut, 1827. A palm-leaf book in Malayalam is being copied; the copy ends up with an Englishman named Charles Whish. Five years later, in London, his paper says infinite series for the circle "originated in Malabar", and that Europe knew them only through Newton's "fluxions". He was right about the series. He was wrong about who wrote them. And he promised a second paper on the proofs that, as far as anyone can find, he never published. I opened his paper, the critical edition of the Yuktibhasa, and Leibniz's 1682 article. Was it calculus? Did the Jesuits carry it to Europe? Here is what the documents prove, and what they don't.