Most third declension adjectives (as distinct from nouns) have ablative signulars ending in -i. An important exception in classical Latin is the comparative adjective, which has abl. sing. in -e. But terms like a priori, a posteriori, and a fortiori may come from late Latin or medieval Latin, where that exception had been "normalized." Languages do change over time, and Cicero, great as he was, is not the eternal archetype of the language.
Comments by timmerd
timmerd commented on the word a priori
Most third declension adjectives (as distinct from nouns) have ablative signulars ending in -i. An important exception in classical Latin is the comparative adjective, which has abl. sing. in -e. But terms like a priori, a posteriori, and a fortiori may come from late Latin or medieval Latin, where that exception had been "normalized." Languages do change over time, and Cicero, great as he was, is not the eternal archetype of the language.
March 26, 2012