There is nothing whatever in Existence but immediate and living Thought:—Thought, I say, but by no means a thinking substance, a dead body in which t… - Johann Gottlieb Fichte

Of what I am, I know no more than that I am, but here no tie is necessary between subject and object. My own being is this tie, I am at once the subject knowing, and the object known of; and this reflection or return of the knowledge on itself is what I designate by the term I, if I have any determinate meaning.

Upon the progress of knowledge the whole progress of the human race is immediately dependent: he who retards that, hinders this also. And he who hinders this, —what character does he assume towards his age and posterity? Louder than with a thousand voices, by his actions he proclaims into the deafened ear of the world present and to come —"As long as I live at least, the men around me shall not become wiser or better; — for in their progress I too, notwithstanding all my efforts to the contrary, should be dragged forward in some direction; and this I detest I will not become more enlightened, — I will not become nobler. Darkness and perversion are my elements, and I will summon all my powers together that I may not be dislodged from them."

Since it cannot be overlooked by the Doctrine of Knowledge that Actual Knowledge does by no means present itself as a Unity, such as is assumed above but as a multiplicity, there is consequently a second task imposed upon it, — that of setting forth the ground of this apparent Multiplicity. It is of course understood that this ground is not to be derived from any outward source, but must be shown to be contained in the essential Nature of Knowledge itself as such; — and that therefore this problem, although apparently two-fold, is yet but one and the same, — namely, to set forth the essential Nature of Knowledge.