Aristotle believed an impression is left on a semi-fluid bodily organ that undergoes several changes in order to make a memory.
ˈæɹɪstˌɑːɾəl bᵻlˈiːvd ɐn ɪmpɹˈɛʃən ɪz lˈɛft ˌɔn ɐ sˈɛmaɪflˈuːɪd bˈɑːdili ˈɔːɹɡən ðæt ˌʌndɚɡˈoʊz sˈɛvɹəl tʃˈeɪndʒᵻz ɪn ˈɔːɹdɚ tə mˌeɪk ɐ mˈɛmɚɹi.