Not treekisser, but I would imagine personifications would be somewhat like Gaiman's Endless. Dream, and the like. Rather than having a character or god(dess) of wisdom, you have an archetypal persona you have created for yourself.
Yes, but honestly, if you go back far enough, the ideas we have of deities, likely started out like this. One person's ideas as to how/what/who the gods are/were. They likely started out as stories told by one person, which made some sort of sense to the people, and they stuck. Or rather the myths likely started out this way.