Where there is no definite quality, knowledge is impossible. Mere light is mere darkness.
 Georg Wilhelm Friedrich Hegel, Science of Logic (1816). copy citation

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Author Georg Wilhelm Friedrich Hegel
Source Science of Logic
Topic darkness quality
Date 1816
Language English
Reference
Note Translated by William Wallace
Weblink http://www.gutenberg.org/files/55108/55108-h/55108-h.htm

Context

“but without definite feature, that is, without negation, contained in the notion, there can only be an abstraction. When the notion of God is apprehended only as that of the abstract or most real being, God is, as it were, relegated to another world beyond: and to speak of a knowledge of him would be meaningless. Where there is no definite quality, knowledge is impossible. Mere light is mere darkness. The second problem of rational theology was to prove the existence of God. Now, in this matter, the main point to be noted is that demonstration, as the understanding employs it, means the dependence of one truth on another.” source