Academica is a treatise on Academic Skepticism and its differences with Stoicism, written by Marcus Tullius Cicero in 45 BCE, two years before he was killed on the order of Mark Anthony, and the same year his beloved daughter Tullia had died in childbirth. No wonder Cicero wrote, at the beginning of Academica:
“Having been stricken to the ground by a most severe blow of fortune, and being discharged from all concern in the republic, I seek a medicine for my sorrow in philosophy.” (I.3)
In part I of this essay I have covered book I of Academica, and we have seen what Cicero had to say on Stoicism from an Academic Skeptic perspective. I have also given a short introduction to the Skeptics’ philosophy, discussing in what sense skepticism about knowledge can lead to ataraxia, and therefore how Academic Skepticism is not just a theoretical position, but also a philosophy of life, on par with Stoicism, Epicureanism, and the rest. Here I will comment on selected quotes from book II, again with particular reference to what Cicero has to say regarding Stoicism.
The first bit is interesting for a number of reasons. To begin with, it is a rare example of an explicit report on a disagreement between schools of thought about logic, rather than ethics. Moreover, it highlights how the Stoics were far more practically bent than other schools. Cicero is commenting on how the Stoic logician Chrysippus reacted to the famous Sorites paradox, the original formulation of which is attributed to Eubulides of Miletus, a member of the Megarian school which actually influenced Zeno of Citium, the founder of Stoicism.
“Sorites” comes from the Greek from heap, since the most famous rendition of the paradox involves the question of when a group of grains of sand becomes a heap. Here is the argument leading to the paradox:
Premise 1: 1,000,000 grains of sand is a heap of sand
Premise 2: A heap of sand minus one grain is still a heap
Repeat Premise 2 a number of times, and you get:
So 999,999 grains is a heap.
If 999,999 grains is a heap then 999,998 grains is a heap.
So 999,998 grains is a heap.
... So 1 grain is a heap.
Turns out, if we grant the (reasonable) initial premise that a million grains of sand do indeed form a heap, then we are forced to grant the conclusion that one grain is also a heap. Which is obviously absurd. Hence the paradox.
There are countless variations of the Sorites paradox, which basically arises every time there are value predicates at play, like “heap,” or “tall,” or “bald,” and so forth. Now, here is what Cicero says about Chrysippus’ take on the problem:
“[In response to Sorites paradox] Chrysippus’s plan is, when he is interrogated step by step (by way of giving an instance), whether there are three, or few, or many, to rest a little before he comes to the ‘many.’” (II.29)
In other words, Chrysippus took a pragmatic approach: if it looks like a heap, I’ll call it a heap; if it doesn’t, I’ll call it something else. While Cicero is making fun of the Stoic take on this, he is also missing the point. Logically speaking, there is no good solution to the paradox (though lots have been proposed!), but it doesn’t matter because nobody’s life is going to be made better by solving the problem. Chrysippus, let us remember, was no slacker when it came to logic, but he also adopted the typically pragmatic Stoic attitude that philosophy (including logic) is supposed to make us better human beings. Intellectual puzzles, by contrast, waste our time and distract us from the cultivation of virtue. Seneca makes the same point:
“I should deem your games of logic to be of some avail in relieving men’s burdens, if you could first show me what part of these burdens they will relieve.” (Letters to Lucilius, XLVIII.9)
The debate then shifts to what Stoics and Academic Skeptics considered the sources of knowledge, i.e., to epistemology. Cicero explains:
“Nor do we [Academics] speak against the senses differently from the Stoics, who say that many things are false, and are very different from the appearance which they present to the senses.” (II.31)
The dispute here is whether some “impressions” that we have about the world rise to the level of what the Stoics called “kataleptic,” that is, indubitable. The Skeptics agreed with the Stoics that much of our knowledge comes from the senses, and also that our senses can be deceived. The Skeptics though took this to imply that human knowledge is impossible, while the Stoics had two more layers to add to the issue. First, they introduced the concept of kataleptic impressions. Here is an example: assume it is about noon now; go outside and try to convince yourself that it is, in fact, midnight. It’s impossible. Your perception that it’s midday it’s just too strong. Kataleptic impressions can also originate internally, without the trigger of sensorial experience. For instance, try to convince yourself that 2+2=5. You can’t, your “grasping” (which is what “katalepsis” means) of the truth that 2+2=4 is too strong.
Second, the Stoics thought that actual knowledge, what they called episteme, actually requires not just the firm grasping of individual notions, but the comprehension of how those notions fit into the general web of knowledge that describes the cosmos. Nowadays we refer to that sort of knowledge as scientific, though the Stoics thought it was reserved for the sages. (And no, I wouldn’t argue that modern scientists are sages.)
The Skeptics, of course, pointed out that just because one is having what looks like a kataleptic impression it still doesn’t mean he could not be wrong. I may be hallucinating, for instance, in which case I may well confuse night and day. Or I may have some severe neurological disturbance, because of which I may convince myself that 2+2=5. And so on. Here the Stoic response was something along the lines of the one we have seen adopted by Chrysippus when it came to logic: yeah, yeah, theoretically one could be a brain in a vat. But, really, how are you going to live your life if you keep thinking like that? Accordingly, the Stoics accused the Skeptics of being unable to make decisions and to act, on account of their conviction that there is no such thing as human knowledge.
In reality, the two schools — through repeated interactions and reciprocal challenges — came to positions that were not very different from each other. Carneades, the most influential of the Academic Skeptics, avoided the trap of radical skepticism by claiming that some things are more likely than others, and that it is on the basis of this likelihood that one can make decisions to act. But this is really not that different from the Stoic acknowledgement that while one can be mistaken about kataleptic impressions (unless one is a sage), they are still one of our best guides to action.
“The Stoics say that the senses themselves are assents; that desire comes after them, and action after desire.” (II.33)
Here we find summarized an important bit of Stoic psychology, which has very practical consequences. Cicero is saying that the Stoics recognize a sequence from assent (triggered by a sensorial experience) to desire to action. For instance: I see (via sense experience) a beautiful woman walking by and automatically assent to the proposition that it would be good to have sex with her. This generates a desire to actually have sex, which in turns moves me to approach the woman in question. (Notice that the desire here comes out of the assent to the notion that having sex with beautiful strangers is a good thing.)
Except that after the first stage I have cognitively challenged my impression, reminding myself that I am married and love my wife, and that it would be unethical to betray her trust. So I never develop the desire, nor do I initiate any action. Which really gets to the core of the interplay between psychology and ethics in Stoicism. Much of Stoic training is precisely about challenging our automatic impressions (Epictetus’ discipline of assent), which both alters our desires (discipline of desire and aversion), and leads us to act differently (discipline of action).
Cicero then tells us more about Chrysippus’ writings — a good thing, since none of the primary sources have survived, unfortunately:
“Chrysippus often testifies that there are three opinions only about the chief good which can be defended; he cuts off and discards all the rest. He says that either honor is the chief good, or pleasure, or both combined.” (II.45)
This is interesting because Chrysippus here seems to be summarizing the main conceptual differences among the Hellenistic schools of philosophy. If by “honor” in the quote above we understand virtue (Cicero does use the terms interchangeably here) then we have the following classification:
Virtue is the chief good: Cynicism, Stoicism
Pleasure is the chief good: Cyrenaics, Epicureans
Both virtue and pleasure are chief goods: Aristotelians, Skeptics
Note, of course, that the Stoics did think that pleasure has value (axia), and the Epicureans regarded virtue has having value as well. But their respective definitions of the chief good were as above.
The last bit I wish to comment on returns to the field of epistemology and the issue of what constitutes knowledge. Cicero there tells us about one of the most famous metaphors used by the Stoics:
“And Zeno professed to illustrate [the differences among perception, opinion and knowledge] by a piece of action; for when he stretched out his fingers, and showed the palm of his hand, ‘Perception,’ said he, ‘is a thing like this.’ Then, when he had a little closed his fingers, ‘Assent is like this.’ Afterwards, when he had completely closed his hand, and held forth his fist, that, he said, was comprehension. From which simile he also gave that state a name which it had not before, and called it κατάληψις (katalepsis). But when he brought his left hand against his right, and with it took a firm and tight hold of his fist, knowledge, he said, was of that character; and that was what none but a wise man possessed.” (II.47)
The progression, then, is: perception > assent > comprehension (katalepsis) > knowledge. Most of us can hope for the first three but not the fourth (unless we are sages). Far too many people get stuck at the second stage, and when they give assent to impressions that should be rejected they mis-live their lives.