The following is based on the French translation found in the best Epitome of all things Epicurean in the French language: the 1550-page tome titled Les Epicuriens.
A central concept here is the problem of causal responsibility, and whether this responsibility can be attached to our initial constitution (our nature, our physiology), to the environment, or to our agency.
If one’s nature is responsible for actions, we attach less praise and blame to actions. Epicurus says that there are people who are, by nature, “solidified” and lack malleability (changeability), ergo one does not try to encourage or incite that person to the accomplishment of the most opportune actions, as his or her nature does not allow us to assign causal responsibility.
F. Massi suggests that this malleability or softness, which is hated by the Stoics, is praised as good by Epicurus because it aids against solidification: one who is malleable, flexible, or soft, can make progress and become morally better through education. As a side note, this subject of how being flexible and malleable is a virtue in naturalist philosophy was elaborated during our Taoist Contemplations.
Yet, because of his evil nature, we denigrate and often hate a man so that in the end, in practice our reaction is frequently non-different from blame. The example given in the French-language book Les Epicuriens is that of a shark: we hate the creature, but we do not blame the shark for eating a man because the shark’s initial constitution and the developed product (of the shark’s character) are non-different.
This is the case even if we separate to some degree the first (initial) constitution (or nature) of a man from his product in the course of development, because the initial constitution (a man’s nature, no matter how evil) may sometimes make a way for it to be possible for other things (non-nature, culture, environment, education) to build a developed product, a wholesome character.
This is why we still admonish people who by nature are evil, and we do not fully absolve them of their crimes, we are merely more lenient with them. We do not treat them as we would wild beasts (in the words of Epicurus) because men are not sharks. Members of our species are domesticated creatures. Therefore, we have a bit more expectations of even the least morally developed of our fellow humans than we do of wild beasts.
Many of Epicurus’ reasonings in this book might be (and have been) interpreted to include cats, dogs, horses, and other animals whom we have domesticated, and whose behavior therefore departs from their initial constitution to some extent.
Therefore, there is a correlation between the initial constitution (or nature) of a creature, who may have anti-social or vicious tendencies, and the attribution of causal responsibility.
But as man matures, it ceases to be the case that he acts purely on impulse. This is moral development, and it transforms the initial constitution. We can therefore evaluate and describe man’s moral evolution.
According to Epicurus’ early theory concerning our instinctive, subconscious drives, we carry within us certain tendencies, or dispositions, which in turn inform our actions. Epicurus claimed that, in the process of moral development, one has the power to change one’s beliefs, and even to atomically change one’s mind. This, today, is being researched under the science of neuroplasticity. The goal of Epicurean therapy is, therefore, to transform our dispositions in order to have a final developed product, which is a good and happy character that experiences ataraxia and is free from irrational or superstitious fears.
People have, from the beginning, the germs of good, bad, and neutral tendencies. There comes a time when these seeds bear fruit, and that depends absolutely on us. We admonish, combat, and transform each other as if we had the causal responsability in ourselves and not just in our initial constitution.
Causal responsibility resides on agents, not merely on actions that are caused by previous movements, for it is agents who are observed to stop themselves from doing the evil things of which their nature is capable.
If a determinist argues against this, he can choose to continue admonishing and praising others, but will still leave intact our anticipation of responsibility–upon which our judgements of praise and blame are constructed–and will only have re-named it.
And, if all things are by necessity, then the determinists must not give themselves the responsibility for reasoning soundly, and give us the blame for reasoning unsoundly, therefore attributing to their adversaries the causal blame for their own wrong reasoning.
If all actions are determined by atoms (by nature), then our moral and social practices of admonition would make no sense. Therefore, Epicurus’ (determinist) adversary would have to renounce his moral, social and educational practice due to the incompatibility of theory and action.
In fact, the determinists’ actions and opinions would constantly be in contradiction, because we constantly stop ourselves and others from doing bad or stupid things, in spite of our own impulses and desires.
Our contribution (to our actions) consists on perceiving that, if we do not clearly understand the rules and criteria of all the things done by virtue of our opinions, and instead we follow our impulses irrationally, all is lost to excess and fault. – Epicurus
There are many things that are done with the contribution of nature, as well as many things which are done without its contribution; and also many things which are done by putting our nature in order (via restraining, educating, or training our initial constitution), and many other things are done where nature herself serves as guide.
Both causal responsibility and necessity procure each other. We are causally responsible to seek out the principle, rule and criterion by which to act, little by little.
Moral Responsibility and Moral Development in Epicurus, by Susanne Bobzien