"The Indian origin of infinite series, found in widely distributed texts, has long been publicly known to Western scholars (Whish 1832). Recent research (Raju 2007) has shown that these Indian developments really did amount to the calculus. (This brings to the forefront various epistemological issues, and the very philosophy of mathematics taken for granted in Western discourse.) This research has also pushed the historical origin of the calculus in India much further back, to the 5th c. CE Āryabhat.a, and his method of obtaining sine values by numerically solving the corresponding differential equation using a finite difference technique."