What did Thomas Bradwardine do?

Answer 1

Thomas Bradwardine (c. 1290 - 26 August 1349), often called "the Profound Doctor", was an English scholar and courtier and, very briefly, Archbishop of Canterbury.

Merton College sheltered a group of dons devoted to natural science, mainly physics, astronomy and mathematics, rivals of the intellectuals at the University of Paris. Bradwardine was one of these Oxford Calculators, studying mechanics with William Heytesbury, Richard Swineshead, and John Dumbleton. The Oxford Calculators distinguished kinematics from dynamics, emphasizing kinematics, and investigating instantaneous velocity. They first formulated the mean speed theorem: a body moving with constant velocity travels the same distance as an accelerated body in the same time if its velocity is half the final speed of the accelerated body. They also demonstrated this theorem-the essence of "The Law of Falling Bodies"- long before Galileo, who is generally credited with it.

The mathematical physicist and historian of science Clifford Truesdell, wrote:The now published sources prove to us, beyond contention, that the main kinematical properties of uniformly accelerated motions, still attributed to Galileo by the physics texts, were discovered and proved by scholars of Merton college .... In principle, the qualities of Greek physics were replaced, at least for motions, by the numerical quantities that have ruled Western science ever since. The work was quickly diffused into France, Italy, and other parts of Europe. Almost immediately, Giovanni di Casaleand Nicole Oresme found how to represent the results by geometrical graphs, introducing the connection between geometry and the physical world that became a second characteristic habit of Western thought ..."

In Tractatus de proportionibus (1328), Thomas Bradwardine extended the theory of proportions ofEudoxus of Cnidus to anticipate the concept of exponential growth, later developed by the Bernoulli andEuler, with compound interest as a special case. Arguments for the mean speed theorem (above) require the modern mathematical concept of limit, so Bradwardine had to use arguments of his day. Mathematician and mathematical historian Carl O. Boyer writes, "Bradwardine developed the Boethian theory of double or triple or, more generally, what we would call 'n-tuple' proportion".

Boyer also writes that "the works of Bradwardine had contained some fundamentals of trigonometrygleaned from Muslim sources". Yet "Bradwardine and his Oxford colleagues did not quite make the breakthrough to modern science" (Cantor 2001, p 122). The most essential missing tool was calculus.