Most people if you ask them if they believe that everything has a cause, they’ll likely say yes. Most people if you ask them if they believe that everyone is basically morally responsible, they’ll likely say yes.
The ancient Stoics believed everyone was morally responsible more or less and that everything including our own behaviors were causally determined. The question of course is how can humans be morally responsible and determined at the same time?
The Stoic Chrysippus distinguished between extrinsic causes that are all external to ourselves and intrinsic causes which are internal to our character. Chrysippus used a clever analogy of a cylinder being pushed to roll. Basically, the cylinder’s shape represents our intrinsic character and the force pushing the cylinder represents an external stimulus/impression. In the analogy the cylinder will only roll if two conditions are met: 1. it is pushed and 2. it is round. 1&2 are required for the same effect: rolling. So our character assenting to an impression and the external impression itself is what determines us to have an impulse or not. If we are stimulated but we do not respond, we do not act. Only when both conditions are satisfied is an action or impulse caused. Even if the act is to not do anything at all. Essentially, the idea is that everything is fated but we help co-fate our future. The shape of our characters is where we possess some control and that’s where we find moral responsibility.
Something counter-intuitive that the Stoics would say is, yes, we have limited freedom to coordinate our future given whether fate allows but on top of that, none of us are truly free except for the Sage. Ancient Stoics believed that if we couldn’t truly be a master of all of our passions and desires, we were a slave to our passions/desires and ultimately are not truly free. So even though Stoicism does make room for soft determinism (the position that moral responsibility and determinism are compatible), it also seems to paradoxically hold a hard determinist position that there is no true freedom for anyone except for the Sage.
So we end with that paradox. We all possess a limited amount of freedom that is compatible with a determinist universe. But ultimately we’re not truly free like the Sage. We’re capable of being free in a sense but not truly so. So we still have to live with the idea that each of us each bear responsibility even if truly the Sage only bears true responsibility. We’re living in an illusion of freedom because we’re all still slaves to our desires/passions unless we become truly free from our desires/passions and become Sages.