A third consequence of the basic ontological difference is the contrast in the valuation of the individual on the part of ancient and modern humanism. While the ancient world valued the individual not as an individual but as a representative of something universal, e.g. a virtue, the rebirth of antiquity saw in the individual as an individual a unique expression of the universe, incomparable, irreplaceable, and of infinite significance. It is obvious that these differences created decisive differences in the interpretation of courage. It is not the contrast between renunciation and salvation to which I am referring now. Modern humanism is still humanism, rejecting the idea of salvation. But modern humanism also rejects renunciation. It replaces it by a kind of self-affirmation which transcends that of the Stoics because it includes the material, historical, and individual existence. Nevertheless, there are so many points in which this modern humanism is identical with ancient Stoicism that it may be called Neo-Stoicism. Spinoza is its representative. In him as in nobody else the ontology of courage is elaborated. In calling his main ontological work Ethics he indicated in the title itself his intention to show the ontological foundation of man’s ethical existence, including man’s courage to be. But for Spinoza—as for the Stoics—the courage to be is not one thing beside others. It is an expression of the essential act of everything that participates in being, namely self-affirmation.
The doctrine of self-affirmation is a central element in Spinoza’s thought. Its decisive character is manifest in a proposition like this: “The endeavour, wherewith everything endeavours to persist in its own being, is nothing else but the actual essence of the thing in question” (Ethics iii. prop. 7). The Latin word for endeavor is conatus, the striving toward something. This striving is not a contingent aspect of a thing, nor is it an element in its being along with other elements; it is its essentia actualis. The conatus makes a thing what it is, so that if it disappears the thing itself disappears (Ethics ii, Def. 2). Striving toward self-preservation or toward self-affirmation makes a thing be what it is. Spinoza calls this striving which is the essence of a thing also its power, and he says of the mind that it affirms or posits (affirmat sive ponit) its own power of action (ipsius agendi potentiam) (iii. prop. 54).