Since the time of Simplicius in the sixth century, commentators have tried to prove that Aristotle was right in naming just ten categories, and just the ten, which he did name. They used a variety of principles to divide all beings into Aristotle’s ten categories.
In the Arabic-speaking world, Avicenna (d. 1037) proposed a division of beings into Substance, Quantity, and Quality (which can be conceived without regard to anything other than their substance), and the remaining seven categories (whose conception requires reference to something other than their substance). This two-plus-seven division of accidents was taken up in the West by Albert the Great (d. 1280).
Robert Kilwardby (d. 1279) proposed a three-plus-three-plus-three division, based on a distinction between what attached to a substance intrinsically or extrinsically or in a mixed mode, and between what concerned the subject’s matter or form or the composite of matter and form. Kilwardby’s division was later reproduced by Walter Burley (d. 1344).
In 1266, William of Moerbeke translated Simplicius’ Categories commentary into Latin. Thomas Aquinas, whose derivation of the ten categories was based on the different modes of predication, consulted this translation: a predicate either indicates what its subject is substantially, or else it is in the subject, or else it is outside the subject. A predicate that is in the subject is so either absolutely (following either from the subject’s matter or from its form) or it is in the subject relatively. A predicate that is outside its subject is either wholly outside the subject (either not as a measure of the subject or as a measure - and then either as a measure of time, or of place in relation to the subject’s parts, or of the whole subject), or outside of it in the way that Action and Affection are outside their subject.
John Duns Scotus thought the method of division could never demonstrate the sufficiency of the ten categories, though he believed they were only ten.
Like Scotus, William Ockham (d. 1347) rejected the opinion of those who sought to construct a deduction of the ten categories from first principles. He believed it was necessary only to have categories of Substance and Quality, the remaining categories being reducible to these. John Buridan (d. c. 1361) thought all the categories were reducible to Substance, Quantity, and Quality.
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