Page:O. F. Owen's Organon of Aristotle Vol. 2 (1853).djvu/278

 626 Yet more, genus is predicated in reference to what a thing is, but difference in reference to what kind of a thing it is, as was observed before; besides there is one genus according to every species; e. g. of man, animal (is the genus), but there are many differences, as rational, mortal, capable of intellect and science, by which he differs from other animals. Genus also is similar to matter, but difference to form: however since there are other things common and peculiar to genus and difference, these will suffice.

and species possess in common, (as we have said,) the being predicated of many things, but species must be taken as species only, and not as genus, it the same thing be both species and genus. Moreover, it is common to them both to be prior to what they are predicated of, and to be each a certain whole; but they differ, because genus indeed comprehends species, but species are comprehended by, and do not comprehend genera, for genus is predicated of more than species. Besides, it is necessary that genera should be presupposed, and when formed by specific differences, that they should consummate species, whence also genera are by nature prior. They also co-subvert, but are not co-subverted, for species existing, genus also entirely exists, but genus existing there is not altogether species; genera too, are indeed univocally predicated of species under them, but not species of genera. Moreover, genera exceed, from comprehending the species which are under them, but species exceed genera by their proper differences; be-