To Explain God as Unexplainable

"Quia de deo scire non possumus quid sit, sed quid non sit, non possumus considerare de deo, quomodo sit sed quomodo non sit."

This is St. Thomas Aquinas' introduction to this whole Summa Theologica: "Since we cannot know what God is, but only what God is not, we cannot consider how God is but only how He is not."

At different points in my life, I've been pretty sure that we can know exactly who and what God is. We can define him quite precisely. We can come up with a list of attributes. We c...