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Today is John Wallis' Birthday!
Happy Birthday

Born:  November 23, 1616
in Ashford, Kent, England

Died:  October 28, 1703
in Oxford, England

Savilian Professor of Geometry


Pillars of Wallis'  Contributions

  • Induction
                                       Wallis vs. Hobbes
    Wallis' arch rival, Thomas Hobbes, was vociferiously devoted to deductive reasoning based on Euclidean structures; thus, Hobbes refuted all proof based on induction.
    Wallis was more pragmatic.  He won respect by showing Hobbes' attempts to "square the circle" were not possible.

    Today mathematicians accept Hobbes' assertion that a rule that holds for a certain number of cases says nothing about whether it will hold for other cases not tested.  Yet Wallis' premise of induction opened the door for experimental scientists in the Royal Society to move forward with different methods of investigation.

    In his Treatise on Algebra (1685), Wallis writes "not so much to shew a Method of Demonstrating things already known . . . . as to shew a way of Investigation of finding out things yet unknown."

  • Algebraic Notation
    Wallis' rather unorthodox use of infinitesimal mathematics involved ideas from Cavalieri, Torricelli, Fermat, Bacon and others.  Thus we find symbols for communication of powerful ideas in his writings.   infinity          wallis series

    The NCB thanks the Huntington Library, San Marino, California, for the image of Wallis.