Phenomenology of Spirit, Preface, paragraph 33

That which is imagined becomes the property of pure self-consciousness, this elevation to generality. Yet this is merely one side; it is not yet finished culture. The manner of study in ancient times had this distinction from that of modern times, that the former was the actual thorough education [Durchbildung] of the natural consciousness. Testing separately every aspect of its existence, philosophizing about everything it came across, it made itself into a thoroughly activated generality. In modern times, by contrast, the individual finds the abstract form ready-made. The effort to grasp it and make it his own has more the character of the unmediated ejection from the inward out, and the piecemeal production of the general, than a procession from the inward out, from the concreteness and multiplicity of existence. Hence now the task before us consists not so much in purifying the individual from the immediate sensorial manner, turning it into cogitated and thinking substance, but rather the very opposite: cancelling fixed, determined thoughts so as to actualize and inspire the universal. But it is much more difficult to render fixed thoughts fluid than to do so with sensorial existence. The reason lies in what was said before. The I, the power of the negative or pure reality, has such determinations as its substance and element of its existence; sensorial determinations, by contrast, are only impotent abstract immediacy, or being as such. Thoughts become fluid by pure thinking, this inward immediacy, recognizing itself as a moment, or by pure self-certainty abstracting from itself – not leaving itself behind, setting itself to one side, but surrendering the fixedness of its self-positing, both the fixedness of the pure concrete, which the I itself is over against distinct content, and the fixedness of distinctions, which, set in the element of pure thought, participate in that unconditionality of the I. Through this movement, pure thoughts become concepts, and only then are what they in truth are, self-movements, circles, that which is their substance, spiritual entities.