Heytesbury me ētahi atu mathematically whakaritea te tawhiti hipoki e te tinana whakawhiwhia e ōrite whakatere nekehanga (i teie mahana whakaoti i roto i te whakaurunga), kī e "he tinana nekehanga ōrite whiwhi ngaro ranei e tāpiri [o tere] ka haere i roto i te tahi mau wa [te tawhiti] rite tonu ki taua e ka haere i roto i te wa tonu ki te mea e nekehanga tonu i roto i te taua wa". Oresme o Paris, me te Italian Giovanni Casali takitahi whakaratohia pānuitanga whakairoiro o tenei hononga tataitia, e tohu ana i te [he tinana] ki te... i nekehanga ōrite i te taua nekehanga i roto i taua wa. He aha i whakamātauria e ia William Heytesbury i muri i te whakamātautau pāngarau i runga i te tāpiri o te wāhi o te tinana ōrite, e whakaatu ana i te āheinga o te nekehanga ōrite rite tonu i roto i te wā, i roto i te wā, i te mea i kitea e ia i roto i te tāpiri o te wāhi o te tinana ōrite rite tonu i
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