This makes his logical system considerably different from the Aristotelian/Neo-Platonic systems of the Middle Ages, since for the latter the predicative relation of any sentence of the subject/copula/predicate form had to be understood as modally determined by the particular nature of the predicable corresponding to the predicate (i.e., its species, genus, difference, proprium, accident).
For instance, at rank Genus differences between MTR and LCA range from 27.54% for dataset M3 coverage 4× to 89.37% for dataset M2, coverage 1×.
This means that the within-genus difference in Spirogyra exceeds the differences among the remaining genera.
This means, first of all, that a genus-difference definition of a thing, which does not identify really distinct parts in it, cannot serve as a middle term in demonstration.
These combine to reduce complexities caused by inter-genus differences in coral metabolism and varying responses to temperature changes, while still covering a significant climate gradient (over 10° of latitude 25° of longitude).
Same genus, different species".
Indeed, he insists that nothing of interest follows for a demonstration from the real definition of a subject giving its genus and difference.
He then undertakes an exhaustive survey of the various types of "utterance (lafz)." Following Porphyry's Isagoge, he classifies all predicates or terms (maqulat) into genus, species, difference, individual, proper accident, and common accident.
Even so, he does not use this logical machinery to explain the relationship between absolute and non-absolute categories, but only to clarify the relations between genus and difference, essence and being (esse).
The question is divided into eight articles, where Aquinas argues that God (1) is not a body, and furthermore involves no composition (2) of matter and form, (3) of quiddity (essence, nature) and subject, (4) of essence and being (esse), (5) of genus and difference, or (6) of subject and accident.
Thus, Ockham believes that the set of those predicates that involve no ontological commitment (that is to say, predicates that do not signify anything extramental other than merely the substance itself) includes the Aristotelian genus, specific difference, and proprium (necessary but non-defining property) (see e.g. Moody [1935], 97-106, 145 51).
