<P> Eventually three sub-classes of "things indifferent" developed: things to prefer because they assist life according to nature; things to avoid because they hinder it; and things indifferent in the narrower sense . The principle of adiaphora was also common to the Cynics and Sceptics . The doctrine of things indifferent was revived during the Renaissance by Philipp Melanchthon . </P> <P> Philosophy for a Stoic is not just a set of beliefs or ethical claims, it is a way of life involving constant practice and training (or askesis, see asceticism). Stoic philosophical and spiritual practices included logic, Socratic dialogue and self - dialogue, contemplation of death, training attention to remain in the present moment (similar to some forms of Eastern meditation), and daily reflection on everyday problems and possible solutions . Philosophy for a Stoic is an active process of constant practice and self - reminder . </P> <P> In his Meditations, Marcus Aurelius defines several such practices . For example, in Book II. I: </P> <P> Say to yourself in the early morning: I shall meet today ungrateful, violent, treacherous, envious, uncharitable men . All of the ignorance of real good and ill...I can neither be harmed by any of them, for no man will involve me in wrong, nor can I be angry with my kinsman or hate him; for we have come into the world to work together...</P>

What best describes the philosophy of the stoics