Again, not all qualities can be regarded as Reason-Principles: chronic disease cannot be a Reason-Principle. Perhaps, however, we must speak in such cases of privations, restricting the term “Quantities” to Ideal-Forms and powers. Thus we shall have, not a single genus, but reference only to the unity of a category. Knowledge will be regarded as a Form and a power, ignorance as a privation and powerlessness.
On the other hand, powerlessness and disease are a kind of Form; disease and vice have many powers though looking to evil.
But how can a mere failure be a power? Doubtless the truth is that every quality performs its own function independently of a standard; for in no case could it produce an effect outside of its power.
Even beauty would seem to have a power of its own. Does this apply to triangularity?
Perhaps, after all, it is not a power we must consider, but a disposition. Thus, qualities will be determined by the forms and characteristics of the object qualified: their common element, then, will be Form and ideal type, imposed upon Substance and posterior to it.
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