  To appreciate Marcus’s distinctive contribution to the question of how to live as a Stoic, it will be useful to begin with a background in early Stoic ethics.  Stoicism teaches that virtue is the only good for oneself, that vice is the only evil, and that everything else is indifferent so far as one’s happiness is concerned. That is to say, only virtue can contribute to our happiness; only vice can contribute to our unhappiness. Poverty, ill-repute, and ill-health are not bad, for their possession does not  make us unhappy; wealth, fame and good are not good because their possession does not make us happy. If one asks, ‘how shall I act? On what can I base my choices between health and sickness, wealth and poverty, so that my choices are rational and not arbitrary?’, then the textbook Stoic answer is that among indifferents some are to be preferred as being in accordance with nature (Diogenes Laertius vii.101–5; Arius Didymus 7a–b, Epictetus ii.6.9 [for these passages see Long and Sedley 1987, section 58]). So whereas it is absolutely indifferent how many hairs one has on one’s head or whether the number of stars in the sky is even or odd, we do, and in most cases should, prefer and select wealth, fame and good health over poverty, ill-repute and sickness, because these are (in most cases) in accordance with nature.  Cicero gives one reason why there must be value-differences among indifferents: if everything aside from virtue and vice were absolutely indifferent, the perfected rationality of the Stoic wise person would have no function to carry out (On Ends iii.50). Wisdom’s exercise would consist in flipping coins to select one indifferent over another.