εἴδος

ταύτας δὲ τὰς σχέσεις ἐκάλεσαν οἱ παλαιοὶ ὕλας, οἷς τῆς τοὐτων ἐμέλησεν τεχνολογίας, διότι ὥσπερ ἡ ὕλη συναναφάινεται τοῖς εἴδεσιν, οὕτως καὶ ἡ τοιάδε σχέσις συναναφάινεται τῷ εἴδει τῶν προτάσεων.
The ancients, who cared about these kinds of things, called these relations matters, because just as ideas make matter manifest, so such a relation is made manifest by the idea of a proposition.
This is sort of pun ideas… idea. I think they should be taken in different meanings.

He’s talking about form (εἶδος) in its Aristotelian sense (form vs. matter). Just as matter appears together with forms, so this type of logical category (σχέσις) appears together with the forms of the propositions [propositions in Aristotelian logic]. I.e., when you utter a proposition, you also indicate the logical category it belongs to—a relationship analogous to that between form and matter. τεχνολογία refers to specialized study.

I would hope you’ve read Aristotle before trying this!

actually I have but not as many times as Avicenna who had read the Metaphysics forty times before he understood anythin.