e ("Newton, Sir Isaac", Biographical Encyclopedia of Scientists, 980).
             In 1665, at Trinity, Newton developed the binomial theorem, a rule allowing the square of the sum of two functions to be written as a series of terms. Later on, the plague hit the area Newton was in and had to go home ("Newton, Sir Isaac", Biographical Encyclopedia of Mathematicians, 394). Newton's binomial theorem helped himself develop a method to determine the sum of a power series of terms, which eventually led to the invention of calculus. In 1671, he circulated a manuscript entitled "Methodus Fluxonium et Serierum Infinitarum" describing his method. Later on, the Manuscript was published as Method of Fluxions and Infinite Series (1736), which was after his death ("Newton, Sir Isaac", Biographical Encyclopedia of Mathematicians, 394). The reason Newton started to develop calculus because he wanted to investigate a fact of nature and he was unable to because the current mathematics available to him was inadequate. Calculus
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