P20: The more each one strives, and is able, to seek his own advantage, i.e., to preserve his being, the more he is endowed with virtue; conversely, insofar as each one neglects his own advantage, i.e., neglects to preserve his being, he lacks power.

Dem.: Virtue is human power itself, which is defined by man’s essence alone (by D8), i.e. (by IIIP7), solely by the striving by which man strives to persevere in his being. So the more each one strives, and is able, to preserve his being, the more he is endowed with virtue.

And consequently (by IIIP4 and P6), insofar as someone neglects to preserve his being, he lacks power, q.e.d.

Schol.: No one, therefore, unless he is defeated by causes external, and contrary, to his nature, neglects to seek his own advantage, or to preserve his being. No one, I say, avoids food or kills himself from the necessity of his own nature. Those who do such things are compelled by external causes, which can happen in many ways. Someone may kill himself because he is compelled by another, who twists his right hand (which happened to hold a sword) and forces him to direct the sword against his heart; or because he is forced by the command of a Tyrant (as Seneca was) to open his veins, i.e., he desires to avoid a greater evil by {submitting to} a lesser; or finally because hidden external causes so dispose his imagination, and so affect his Body, that it takes on another nature, contrary to the former, a nature of which there cannot be an idea in the Mind (by IIIP10). But that a man should, from the necessity of his own nature, strive not to exist, or to be changed into another form, is as impossible as that something should come from nothing. Anyone who gives this a little thought will see it.