Free will and the problem of evil

The great logician Chrysippus tackles both, and comes a bit short

A cylinder, the geometric solid chosen by Chrysippus of Soli to explain his theory of free will. Image from Wikimedia, CC license.

One of the standard “spiritual” exercises that constitute my personal philosophical practice is what the ancient Greeks called anagnosis, that is the reading and studying of ancient texts, to remind ourselves about the roots of our wisdom, such as it is.

In that context, for the last few weeks I’ve been reading a delightful gem known as Attic Nights, by the second century writer Aulus Gellius, a contemporary of Marcus Aurelius. It’s an example of hypomnema, a notebook where one jots down ideas that crossed one’s mind because of experiences, conversations, or readings. Marcus’s own Meditations is considered an example of hypomnema. In the case of Aulus’s book, the title comes from the fact that he started keeping this peculiar philosophical diary one cold night during a period he spent in Attica, the region of Greece where Athens is located.

At any rate, I recently read two short entries, numbered 1 and 2 in book VII of Attic Nights, that caught my attention. They are both about the Stoic Chrysippus of Soli, one of the major logicians of all time and the third scholarch of the original Stoa. Both entries concern Aulus’s notes about one particular book written by Chrysippus and now lost, except for fragments: On Providence. As it happens, I’ve written recently about the Stoic concept of Providence, within the context of my ongoing diatribe with so-called traditional Stoics who maintain—impossibly, in my opinion—that unless one believes exactly what the ancient Stoics believed one cannot therefore refer to oneself as a Stoic at all. So I figured it would be time well spent to meditate a bit on what a master like Chrysippus had to say about metaphysics.

Aulus focuses on two related issues discussed by Chrysippus: the problem of evil and the compatibility (in his mind) between moral responsibility and determinism. Let’s take a look in the same order in which Aulus treats them.

The problem of human evil

The first entry in book VII of Attic Nights begins by summarizing the problem of evil: those who wish to deny the notion of a providential universe argue that the very notion of Providence is antithetical to the existence of evil. Either there is a providential God who cares about us, in which case why would he set up a universe that contains evil, or there is evil but no providential God.

This, of course, is a problem that has plagued Christian thinkers since the historical beginnings of their religion, but Chrysippus’s book shows that the issue was alive and well at least three centuries before Jesus was born, and several centuries more before it became the focus of serious theological discussions within the Church.

Chrysippus distinguishes, as Christians do, between human and natural evil, tackling the human variety first. Here is the excerpt reported by Aulus:

“There is absolutely nothing more foolish than those men who think that good could exist, if there were at the same time no evil. For since good is the opposite of evil, it necessarily follows that both must exist in opposition to each other, supported as it were by mutual adverse forces; since as a matter of fact no opposite is conceivable without something to oppose it. For how could there be an idea of justice if there were no acts of injustice? Or what else is justice than the absence of injustice? How too can courage be understood except by contrast with cowardice? Or temperance except by contrast with intemperance? How also could there be wisdom, if folly did not exist as its opposite? Therefore, why do not the fools also wish that there may be truth, but no falsehood? For it is in the same way that good and evil exist, happiness and unhappiness, pain and pleasure. For, as Plato says, they are bound one to the other by their opposing extremes; if you take away one, you will have removed both.” (Attic Nights, VII.1)

The reference to Plato is interesting, because it pushes back the origin of this discussion by at least another century. Chrysippus may be correct that we wouldn’t have the concept of good without the symmetrical concept of evil. Just like, again maybe, we wouldn’t have the concept of courage without the opposite one of cowardice. But that by no means implies that it is impossible to build an actual world where there is no evil or no cowardice.

Consider some of Chrysippus’s own examples, beginning with justice vs injustice. The Stoics argued that the ideal human society would be made of sages, who would all, always, act justly. In such a society there would, therefore, be no such thing as injustice. And yet this didn’t stop Zeno of Citium, the founder of Stoicism, from conceiving of its possibility.

Or take the truth / falsehood couplet. I can easily conceive a world where people don’t spread fake news and alternative facts, that is, where everyone would speak truthfully. Moreover, the Epicureans certainly did envision the existence of pleasure in the complete absence of pain, and indeed strove to achieve precisely such a state. So, pace Chrysippus the logician, there is no logical contradiction inherent in any of these scenarios. Which means the “why is there evil in a Providential universe?” objection does have force.

(To be fair to Chrysippus, though, at least he did not take the Christian root and blamed human beings for evil, which in Christian theology is allegedly a consequence of the “gift” God gave us of free will. But we’ll get to that topic in a few minutes.)

The problem of natural evil

Next, Chrysippus turns his attention to the issue of natural, i.e., not human-caused, evil. One way to think about this is to ask why a providential God would create a universe where there is disease. Curiously, Chrysippus here does not use the above strategy, though he could have. He might have said something along the lines of, well, we wouldn’t know what health is without disease. Is the fact that he doesn’t go that route perhaps indicative of the possibility that he realized such an argument isn’t too convincing after all? We will never know. Instead, here is what Chrysippus writes in On Providence:

“When [Nature] was creating and bringing forth many great things which were highly suitable and useful, there were also produced at the same time troubles closely connected with those good things that she was creating. … Exactly as, when nature fashioned men’s bodies, a higher reason and the actual usefulness of what she was creating demanded that the head be made of very delicate and small bones. But this greater usefulness of one part was attended with an external disadvantage; namely, that the head was but slightly protected and could be damaged by slight blows and shocks. In the same way diseases too and illness were created at the same time with health.” (Attic Nights, VII.1)

This is essentially the argument used by Plato in the Timaeus to explain away the natural imperfection of the world: the sub-god who created the universe, the Demiurge, had to work within the constraints of the sort of materials he had available, and the result is the sub-optimal world we see around us. This is not a bad response, actually, as it invokes a sophisticated modern concept found in both evolutionary biology and material science: that of constraints. An engineer, or natural selection, cannot create “perfect” artifacts  or living organisms, because they have to work within specific constraints imposed both by the accessible materials and by the very laws of physics. The implication, however, is that the Stoic God (or the Demiurge, in Platonism [1]) was at the very least not all-powerful, otherwise he could, and presumably would, have done better.