Stat affects - Intelligence

Hey, A friend of mine sincerely believes that the INT stat, alters enemies/players magic defence stat. I am FAIRLY certain that it does not, and citing the stat tooltips does not convince him. DOES Intelligence alter anything besides magic attack potency? Or is he overthinking?

Easy enough to test with accessories, which I just did for you. INT+40 does nothing for my magic defense, VIT+36 does nothing for my physical defense.

Thanks for that! ^_^