▁test ▁his ▁results ▁- ▁a ▁corner stone ▁of ▁the ▁scientific ▁method , ▁and ▁a ▁continu ation ▁of ▁the ▁work ▁of ▁research ers ▁like ▁Al ▁Batt ani . ▁ ▁Ba con ▁and ▁Gros set este ▁conducted ▁investig ations ▁into ▁opt ics , ▁although ▁much ▁of ▁it ▁was ▁similar ▁to ▁what ▁was ▁being ▁done ▁at ▁the ▁time ▁by ▁Arab ▁sch ol ars . ▁Ba con ▁did ▁make ▁a ▁major ▁contribution ▁to ▁the ▁development ▁of ▁science ▁in ▁medieval ▁Europe ▁by ▁writing ▁to ▁the ▁Pope ▁to ▁encou rage ▁the ▁study ▁of ▁natural ▁science ▁in ▁university ▁courses ▁and ▁compiling ▁several ▁volumes ▁recording ▁the ▁state ▁of ▁scientific ▁knowledge ▁in ▁many ▁fields ▁at ▁the ▁time . ▁He ▁described ▁the ▁possible ▁construction ▁of ▁a ▁teles cope , ▁but ▁there ▁is ▁no ▁strong ▁evidence ▁of ▁his ▁having ▁made ▁one . ▁ ▁Late ▁Middle ▁A ges ▁( AD ▁ 1 3 0 0 – 1 5 0 0 ) ▁The ▁first ▁half ▁of ▁the ▁ 1 4 th ▁century ▁saw ▁the ▁scientific ▁work ▁of ▁great ▁think ers . ▁The ▁logic ▁studies ▁by ▁William ▁of ▁Occ am ▁led ▁him ▁to ▁post ulate ▁a ▁specific ▁form ulation ▁of ▁the ▁principle ▁of ▁par sim ony , ▁known ▁today ▁as ▁Occ am ' s ▁raz or . ▁This ▁principle ▁is ▁one ▁of ▁the ▁main ▁he ur istics ▁used ▁by ▁modern ▁science ▁to ▁select ▁between ▁two ▁or ▁more ▁under det erm ined ▁theories , ▁though ▁it ▁is ▁only ▁fair ▁to ▁point ▁out ▁that ▁this ▁principle ▁was ▁employed ▁explicitly ▁by ▁both ▁Aqu inas ▁and ▁Arist ot le ▁before ▁him