The appellation "Merton Calculators" refers primarily to four men who were students or masters at Merton College, Oxford, in the fourteenth century. They never formed an actual "school" or movement but shared an interest in developing techniques for solving a variety of logical dilemmas and mathematical problems applicable to natural philosophy and theology. "Calculator" was the name given apparently by fifteenth-century Italian Schoolmen to the chronologically last of these authors, Richard Swineshead, and it has been applied retrospectively to John of Dumbleton, Thomas Bradwardine, and William Heytesbury.

Born probably around 1310, John was a native of the village of Dumbleton in Gloucestershire in the diocese of Worcester. He was a fellow of Merton College in 1338. In the Merton Muniments of 1338-1339 he is mentioned along with Heytesbury, John Ashinden, William Sutton, Simon Bredon, and Thomas Buckingham. In the founder's statutes of 10 February 1340 he is named as a fellow of...