 A full understanding of Chrysippus’ attempted resolution of the problem of how anything can be up to us when the history of the world is such that the present chapter of the narrative is inescapable given what has come before is rendered difficult by the lack of clarity around the various kinds of causes. It is clear enough, at least in general terms, what outcome Chrysippus was aiming with respect to human action. In a famous analogy, he treats a person’s character as analogous to the shape of a cylinder. It is true that the world gives us things to react to, just as a person might give the cylinder a shove. But the cylinder rolls, rather than slides, because of its specific shape (i.e. its nature). So too your decisions are your decisions in as much as the kind of person you are makes a difference to what you decide to do. Sure – you are the kind of person that you are in no small part because of what has happened to you previously. But when your decisions play a role in bringing about what you do, the Stoics say that what comes about through fate comes about through you and those actions are ‘up to you’ in some sense appropriate to the notion of responsibility.  That sense is allegedly supplied by the distinction among the kinds of causes introduced above. Detailed scholarly work on the question of free will and determinism in Stoicism seeks to engage with our various sources and attempts to position this very different framework for thinking about causes and causation in relation to our own. A good guide to the terrain is provided by Hankinson, chapters 14 and 15 in Algra, Barnes, Mansfeld &amp; Schofield (1999). Bobzien (1998) is longer and perhaps more difficult for the beginning philosopher, but very authoritative.