  The last of these four behaviors is productive of piety. The key idea in piety is that the cosmos as a whole is providentially designed, and so is as good as it can be, and so its parts are as good as they can be, and so our attitude towards every part ought to be acceptance—or as he sometimes puts it more strongly, love. According to Hadot (1998, 128), Marcus follows Epictetus in distinguishing impulse (hormê) from desire (orexis), and innovates by restricting impulse to the sphere of our activity. Desire, parallel to impulse, is restricted to the sphere of our passivity; thus, we should desire whatever befalls us. Hadot is mistaken here, for according to the Stoics, our reactions to what befalls us are also impulses, and desire is a species of impulse. Marcus says either to restrict desire to what is up to us (ix.7) or to quench (sbêsai) it. Epictetus tells us to refrain from desire for the time being (iii.24.23, 24, 85). The reason to quench desire is the danger of desiring the wrong thing: to desire something is to believe it to be good, and to have a runaway impulse towards it. This also gives us an argument against desiring the things that befall one. We might note that Marcus, in the passage above, recommends not desiring but welcoming (aspazomenê) whatever befalls one. Perhaps we should associate desire (orexis) with pursuing, and welcoming with contentment upon receiving.