A Something is what it is in virtue of its quality, and losing its quality it ceases to be what it is. Quality, moreover, is completely a category only of the finite, and for that reason too it has its proper place in Nature, not in the world of Mind.
 Georg Wilhelm Friedrich Hegel, Science of Logic (1816). copy citation

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

Context

“Quality may be described as the determinate mode immediate and identical with Being—as distinguished from Quantity (to come afterwards) , which, although a mode of Being, [Pg 171] is no longer immediately identical with Being, but a mode indifferent and external to it. A Something is what it is in virtue of its quality, and losing its quality it ceases to be what it is. Quality, moreover, is completely a category only of the finite, and for that reason too it has its proper place in Nature, not in the world of Mind. Thus, for example, in Nature what are styled the elementary bodies, oxygen, nitrogen, &c., should be regarded as existing qualities. But in the sphere of mind, Quality appears in a subordinate way only, and not as if its qualitativeness could exhaust any specific aspect of mind.” source