Of the philosophers who have claimed absolute knowledge, only Spinoza has offered it, not as the reception of a divine revelation, and not as the fulfillment of a historical process, as in Hegel's epistemology, but as a means for intuitively affirming the truth inherent within all of reality.

Reality is susceptible to such an intuition, he said, because every being is a mode of it, or a way that it expresses itself. In other words, for us to come to know the “absolute” is for the absolute to come to know itself. There is thus something basically self-reflexive and introspective about Spinoza’s epistemology.

At the same time, knowledge for Spinoza is always of what he calls God or Nature, which can also be understood as the universe itself.

There are things about God or Nature that simply cannot be denied and that must serve as the basis from which all other knowledge will be derived: that he essentially exists, that he is absolutely infinite, self-causal, conceivable as existing only in and through himself, omnipotent, omniscient, and eternally existing of necessity.

Of the philosophers who have claimed absolute knowledge, only Spinoza has offered it, not as the reception of a divine revelation, and not as the fulfillment of a historical process, as in Hegel's epistemology, but as a means for intuitively affirming the truth inherent within all of reality. Reality is susceptible to such an intuition, he said, because every being is a mode of it, or a way that it expresses itself. In other words, for us to come to know the “absolute” is for the absolute to come to know itself. There is thus something basically self-reflexive and introspective about Spinoza’s epistemology. At the same time, knowledge for Spinoza is always of what he calls God or Nature, which can also be understood as the universe itself.

http://www.iep.utm.edu/spino-ep/