Text 14. The later scholars came and changed the technical terms of logic; and they appended to the investigation of the five universals its fruit, which is to say the discussion of definitions and descriptions which they moved from the Posterior Analytics; and they dropped the Categories because a logician is only accidentally and not essentially interested in that book; and they appended to On Interpretation the treatment of conversion (even if it had been in the Topics in the texts of the ancients, it is none the less in some respects among the things which follow on from the treatment of propositions). Moreover, they treated the syllogistic with respect to its productivity generally, not with respect to its matter. They dropped the investigation of [the syllogistic] with respect to matter, which is to say, these five books: Posterior Analytics, Topics, Rhetoric,   Poetics, and Sophistical Fallacies (though sometimes some of them give a brief outline of them). They have ignored [these five books] as though they had never been, even though they are important and relied upon in the discipline (Ibn-Khaldûn  Muqaddima [1858] 112–113; cf. Ibn-Khaldûn 1958: 3, 142–143).