Both these consequences have occurred, for the books of philosophers are full of examples, now of destruction, now of corruption of the empirical classes of the Practical. The treatment of the doctrine of the virtues or of so-called natural rights affords examples of destruction. Striving to distinguish courage from prudence, or justice from benevolence, or on the other hand, egotism from wickedness, they ended by recognizing that true courage is prudence, true prudence courage; that benevolence is justice, justice benevolence; that egotism is wickedness, wickedness egotism, and so on. In this way, all the virtues became one, the virtue of being virtuous, the will for the good, duty. In like manner, by giving philosophical form to the natural rights of life, of liberty, of culture, of property, and so on, they ended by recognizing that all rights merge in one single right, which is that of existence; which latter, indeed, is not a right, but a fact. The passions were reduced from seventy or eighty classes to six or seven fundamental, but these six or seven were in their turn reduced to two only, pleasure and pain, and of these two; it was finally discovered that they constituted one only--life, which is pleasure and pain together. But virtues, rights, passions, possess value in practical description only in so far as they are multiplicity--their value is always plural, never singular. To reduce them to a single class signifies to annul them, as to blow upon a candle signifies to extinguish it and to remain in darkness; darkness is to be understood as without empirical light. Now the philosopher should certainly destroy empirical ideas, but only in so far as they present themselves as philosophical distinctions, that is, in so far as they are empirico philosophical: and in that case it suffices him to show that they are empirical, without pretending to annul them in their own domain also: _debellare superbos,_ but _parcere subjectis;_ that is, he should spare strangers who remain quietly in their own house. [Sidenote: _Examples: war and peace, property and communism, and the like._]