 Although some medieval theologians — and humanists even more, of course, like Vivès or Rabelais — used the words ‘sophism’ or ‘sophist’ as a derogatory designation for quibbling philosophers, ‘sophisma’ in medieval philosophical literature has a very precise and technical sense. To avoid any confusion with fallacies and badly-constructed arguments, we shall here use the original term ‘sophisma’ rather than the word ‘sophism’ (which even nowadays has a pejorative connotation).