a prioriyoudaoicibaDictYouDict[a priori 词源字典]
1710, "from cause to effect" (a logical term, in reference to reasoning), Latin, literally "from what comes first," from priori, ablative of prior "first" (see prior (adj.)). Used loosely for "in accordance with previous knowledge" (1834).[a priori etymology, a priori origin, 英语词源]