The first important feature of Burley's earlier ontology is his belief that apart from substances, quantities, and qualities, the categories do not contain entities in the full sense of the term, but respectus reales,i.e., real aspects of absolute things.
In especial, he distinguishes between predications in the categories of Substance, Quantity and Quality, which are proper and intrinsic, and those in the other six categories, excluding Relation, which he calls improper and extrinsic.
He derives substance, quantity, and quality from distinct sorts of extramental things, and the other seven categories from distinct modes of being (corresponding to Henry's ratio), assuming a parallel between modes of being and modes of predicating.
The second, inspired to Henry of Ghent, admits that being-in-relation-to-something-else (esse ad aliud), i.e., the mode of being of the seven non-absolute categories, does not involve a res distinct from substance, quantity, and quality, but only their real aspects.
Philosophers in the Middle Ages would call such kinds transcendentals, since they transcend Aristotle's ten categories (substance, quantity, quantity, and the other categories); Gilbert Ryle called them syncategorematic.
This work distinguishes the first four Aristotelian categories (substance, quantity, quality, and relation) as intrinsic and the last six categories as extrinsic.
A prime example is Thomas Aquinas's participation in the rediscovery of Aristotelian categories (e.g., substance, quantity, quality, and relation), even though he exceeded and transformed them in the service of theological, ethical, and sacramental teachings that in turn shaped doctrinal conceptions and formulations in the Catholic church of the West.
That is, qualities are the qualities of substances; quantities are the amounts and sizes that substances come in; relations are the way substances stand to one another.
They include substance, quality, quantity, and relation, among others.
This difference in kind can most naturally be taken as referring to some sort of difference, like the one mentioned about the different kinds of motions and of being in Physics 3.1 201a8-9, with the crucial difference that there the relevant categories are substance, quality, quantity and place, whereas here they are apparently action and passion.
