The Apophatic: Pseudo-Dionysius the Aeropagite figured out that you can express the negative (what is not) in theology, not the positive. That seems to be present in Syriac Neoplatonism (but I need to dig for more. He was most certainly Syrian).
He did not use these exact words, and did not get the idea with clarity, but to me he figured out subtractive epistemology and asymmetries in knowledge. He was the disciple of Proclus the Neoplatonist and repeated the metaphor of making statues by removal.
This solves the problem of happiness, for instance. We know what being unhappy means, and can do rather well with it.
(Peri mystikes theologias)