Nicholas of Cusa, answered from the texts and cited to the page.
God is beyond all affirmation and beyond all negation. This is not radical apophasis in the strict Dionysian form, in which negation is the final and proper mode of God-talk; nor is it the affirmative theology of the analogia entis in which positive attributes are predicated of God through eminence and proportion; nor is it merely the dialectical alternation of cataphasis and apophasis in which we say both that God is X and that God is not X.1
The position is a third way: at the level of ratio, both affirmative and negative theology have their proper place, and both are necessary corrective to each other (DI I.24-26). At the level of intellectus contemplating the Maximum, both are surpassed. The Maximum is "beyond all affirmation and all negation" because affirmation and negation are operations of finite ratio that work within the comparative relations of finite reality, and the Maximum, by being absolutely Maximum, is not in those comparative relations.2
The wall of paradise of De Visione Dei is the place where this transcendence is encountered — not by the work of ratio, which collapses at the wall, but by the intellectus that sees the coincidence of opposites at which the wall is constituted.345
For there is one theology: qua affirmative theology it affirms all things of the One; qua negative theology it denies all things of the One—while qua dubitative theology it neither affirms nor denies, qua disjunctive theology it affirms one alternative and denies the other, and qua conjunctive theology it conjoins opposites affirmingly or else denyingly rejects the opposites conjointly.De Filiatione, p. 355
Since the unqualifiedly and absolutely Maximum (than which there cannot be a greater) is greater than we can comprehend (because it is Infinite Truth), we attain unto it in no other way than incomprehensibly. For since it is not of the nature of those things which can be comparatively greater and lesser, it is beyond all that we can conceive.De Docta Ignorantia I, p. 9
I know only the following: viz., that I know that I do not know— and never can know—what I see. Moreover, I do not know how to name You, because I do not know what You are. And if someone tells me that You are named by this or that name, then by virtue of the fact that he names, I know that [this] is not Your name.De Visione Dei, pp. 703–704
However, in Book One of Learned Ignorance enough (though disproportionally less than could be said) is found stated about these matters..." Ap. 24:19-24. See also DVD 13 (52). 11. Cf. Ap. 20:2-8: "For God is found when all things are left behind; and this darkness is light in the Lord.De Deo Abscondito, p. 309
But when he wonders about how it is that (in the case of things which have limits to their magnitude) if a similarity is posited, then a greater similarity can always be posited ad infinitum: let him consider the dividing of a finite line. For in this case we do not come to an indivisible point, even though we seem to approach it through [dividing] the parts of parts.Apologia Doctae Ignorantiae, pp. 479–480
The relation of Cusa's theology to the Dionysian-Eckhartian apophatic tradition is one of the central questions in Cusa scholarship. McGinn's Harvest of Mysticism (2005) placed Cusa firmly in the late-medieval mystical-theological tradition that runs through Eckhart, Tauler, Ruusbroec, and the Rhineland mystics. Beierwaltes traced the Platonic-Neoplatonic continuity from Proclus through the Areopagite through Eriugena through Eckhart to Cusa. The 'third way' reading that distinguishes Cusa's beyond affirmation and negation from strict apophasis and strict cataphasis is articulated by Casarella, Hudson, Hopkins, and others. The Dupré reading places Cusa in the broader story of the passage to modernity with the apophatic tradition as the deepest medieval inheritance. The Aquinas comparison — Cusa's third way versus the Thomistic analogia entis — is a live live discussion that distinguishes Cusa from the Dominican scholastic tradition.