While it is believed that Aristotle's Poetics originally comprised two books – one on comedy and one on tragedy – only the portion that focuses on tragedy has survived.
wˌaɪl ɪɾ ɪz bᵻlˈiːvd ðæt ˈæɹɪstˌɑːɾəlz poʊˈɛɾɪks ɚɹˈɪdʒɪnəli kəmpɹˈaɪzd tˈuː bˈʊks wˈʌn ˌɔn kˈɑːmədi ænd wˈʌn ˌɔn tɹˈædʒədi ˈoʊnli ðə pˈoːɹʃən ðæt fˈoʊkəsᵻz ˌɔn tɹˈædʒədi hɐz sɚvˈaɪvd.