Speaking of mage, I was hoping to perhaps solicit input on the third arcanum for an acanthus character I was working on. See, he's something of a planner and strategist, who likes to use his fate and time mojo to figure out what's likely to come and plan accordingly, and also to nudge things in his favor. He also has a goal to find and collect as many grimoires and owner-less soulstones as he can, eventually being able to make a mage's library for the grimoires.

I was thinking either Prime or Mind for his third arcanum, with the former leading to some Prime focused legacy, and the latter leading to that chessmaster like one with mind.

Which one would be a better pick for his third arcanum?