Newton's "forced" motion corresponds to Aristotle's "violent" motion with its external agent, but Aristotle's assumption that the agent's effect stops immediately it stops acting (e.g., the ball leaves the thrower's hand) has awkward consequences: he has to suppose that surrounding fluid helps to push the ball along to make it continue to rise even though the hand is no longer acting on it, resulting in the Medieval theory of impetus.
nˈuːtənz "fˈoːɹst" mˈoʊʃən kˌɔːɹɪspˈɑːndz tʊ ˈæɹɪstˌɑːɾəlz "vˈaɪələnt" mˈoʊʃən wɪð ɪts ɛkstˈɜːnəl ˈeɪdʒənt, bˌʌt ˈæɹɪstˌɑːɾəlz ɐsˈʌmpʃən ðætðɪ ˈeɪdʒənts ɪfˈɛkt stˈɑːps ɪmˈiːdɪətli ɪt stˈɑːps ˈæktɪŋ ˈiː.dʒˈiː., ðə bˈɔːl lˈiːvz ðə θɹˈoʊɚz hˈænd hɐz ˈɔːkwɚd kˈɑːnsɪkwənsᵻz: hiː hɐz tə səpˈoʊz ðæt sɚɹˈaʊndɪŋ flˈuːɪd hˈɛlps tə pˈʊʃ ðə bˈɔːl ɐlˈɔŋ tə mˌeɪk ɪt kəntˈɪnjuː tə ɹˈaɪz ˈiːvən ðˌoʊ ðə hˈænd ɪz nˌoʊ lˈɑːŋɡɚɹ ˈæktɪŋ ˈɔn ɪt, ɹɪzˈʌltɪŋ ɪnðə mˈɛdɪˌiːvəl θˈiəɹi ʌv ˈɪmpəɾəs.