This is a critical edition with introduction and indices of the Questiones libri Porphirii, a commentary on Porphyry__s Isagoge attributed to the fourteenth-century logician Thomas Manlevelt. Not... Show moreThis is a critical edition with introduction and indices of the Questiones libri Porphirii, a commentary on Porphyry__s Isagoge attributed to the fourteenth-century logician Thomas Manlevelt. Not much is known about Thomas Manlevelt, but his work is remarkable enough. Following in the footsteps of William of Ockham, Manlevelt stresses the individual nature of all things existing in the outside world. He radically challenges traditional medieval conceptions of the outside world. He applies Ockham__s Principle of Parsimony in an unscrupulous manner to do away with all entities not deemed necessary to preserve. In the end, Manlevelt even maintains that substance does not exist. The introduction to this edition sketches the historical and philosophical background of this logical-semantical text, in which individuality and the accidental play the key role. This edition contributes to our knowledge of the development of Ockhamism on the continent. Moreover, it confronts us with a hitherto hardly known thinker whose ideas may prove to be of more than just historical value. Show less