 Starting from the Stoic dictum that the summum bonum consists of virtue alone and that only virtue is good, Lipsius maintains, following Seneca (Letter LXXI.4), that the supreme good must also be honestum or morally honorable, and that it is limited to the soul, the rational part of man (Manuductio II.20). If everything is judged in relation to the standard of its own good, this standard in man is reason. A man whose soul possesses reason has complete control over good and evil. In contrast to the views of the Platonists and Peripatetics, Seneca considers virtue to be sufficient on its own for the honorable life, and for the virtuous life, man needs to be concerned solely with his own conduct. Like Seneca’s sapiens, Lipsius’s wise man,having control over himself, chooses external things only when they are in accordance with nature and, as such, morally honorable. External things are good because the wise man, in his prudence and virtue, has selected them. Choosing rationally among things which are natural but indifferent with respect to happiness is the foundation of true virtuous action. Because only that which is perfect by nature can be called the good — just as the summum bonum is located in God, who is perfect — the good does not exist in man until both he and his reason are perfected (Manuductio II.22, referring to Seneca, Letter CXXIV).