 In addition, we have to thank him for such copious quotations from the Greek commentaries from the time of Andronicus of Rhodes down to Ammonius and Damascius, that, for the Categories and the Physics, the outlines of a history of the interpretation and criticism of those books may be composed.With a correct idea of their importance, Simplicius made the most diligent use of the commentaries of Alexander of Aphrodisias and Porphyry; and although he often enough combats the views of the former, he knew how to value, as it deserved, his (in the main) sound critical sense.He has also preserved for us intelligence of several more ancient readings, which now, in part, have vanished from the manuscripts without leaving any trace, and in the paraphrastic sections of his interpretations furnishes us with valuable contributions for correcting or settling the text of Aristotle.