▁famous ▁ 1 6 6 7 ▁Tre at ise ▁investig ating ▁the ▁light ▁of ▁reason . ▁Y ac ob ▁is ▁most ▁noted ▁for ▁this ▁eth ical ▁philosophy ▁surrounding ▁the ▁principle ▁of ▁harm ony . ▁He ▁pur port ed ▁that ▁an ▁action ' s ▁mor ality ▁is ▁decided ▁by ▁whether ▁it ▁adv ances ▁or ▁de gr ades ▁overall ▁harm ony ▁in ▁the ▁world . ▁His ▁philosophy ▁is ▁the istic ▁in ▁nature . ▁While ▁he ▁did ▁believe ▁in ▁a ▁de ity , ▁whom ▁he ▁referred ▁to ▁as ▁God , ▁he ▁rejected ▁any ▁set ▁of ▁religious ▁belief s . ▁R ather ▁than ▁der iving ▁belief s ▁from ▁any ▁organized ▁religion , ▁Y ac ob ▁sought ▁the ▁truth ▁in ▁obser ving ▁the ▁natural ▁world . ▁In ▁Hat ata ▁in ▁following ▁in ▁the ▁foot steps ▁of ▁great ▁church ▁f athers , ▁Y ac ob ▁applied ▁the ▁idea ▁of ▁the ▁first ▁cause ▁to ▁his ▁proof ▁for ▁the ▁existence ▁of ▁God . ▁" If ▁I ▁say ▁that ▁my ▁father ▁and ▁my ▁mother ▁created ▁me , ▁then ▁I ▁must ▁search ▁for ▁the ▁cre ator ▁of ▁my ▁parents ▁and ▁of ▁the ▁parents ▁of ▁my ▁parents ▁until ▁they ▁arrive ▁at ▁the ▁first ▁who ▁were ▁not ▁created ▁as ▁we ▁[ are ] ▁but ▁who ▁came ▁into ▁this ▁world ▁in ▁some ▁other ▁way ▁without ▁being ▁generated ." ▁However , ▁the ▁know ability ▁of ▁God ▁does ▁not ▁depend ▁on ▁human ▁intellect , ▁but ▁" O ur ▁soul ▁has ▁the ▁power ▁of ▁having ▁the ▁concept ▁of ▁God ▁and ▁of ▁seeing ▁him ▁ment ally . ▁God ▁did ▁not