 William Crathorn (fl. 1330) was not considered by his contemporaries or later medieval commentators to be of the stature of such thinkers as Aquinas, Henry of Ghent, Scotus, or Ockham; still, his views give a window into some of the skeptical worries extant at the time. He worked at Oxford, flourishing in the generation after Scotus, and during the time of Ockham. Tachau (1988) and Pasnau (1997) discuss his views.