Philoponus questioned Aristotle's teaching of physics, noting its flaws and introducing the theory of impetus to explain his observations.
fˈɪləpˌoʊnəs kwˈɛstʃənd ˈæɹɪstˌɑːɾəlz tˈiːtʃɪŋ ʌv fˈɪzɪks, nˈoʊɾɪŋ ɪts flˈɔːz ænd ˌɪntɹədˈuːsɪŋ ðə θˈiəɹi ʌv ˈɪmpəɾəs tʊ ɛksplˈeɪn hɪz ɑːbzɚvˈeɪʃənz.