Posts by Cassius

Transcript

Cassius:

Welcome to Episode 354 of Lucretius Today. This is a podcast dedicated to the poet Lucretius, who wrote On the Nature of Things, the most complete presentation of Epicurean philosophy left to us from the ancient world. Each week we walk you through the Epicurean texts, and we discuss how Epicurean philosophy can apply to you today. If you find the Epicurean worldview attractive, we invite you to join us in the study of Epicurus at EpicureanFriends.com, where we discuss this and all of our podcast episodes.

We’re continuing in Book Two of Cicero’s Academic Questions, addressing the nature and possibility of knowledge and how that factors into all of our day-to-day decision-making — settling from the very beginning whether happiness or pleasure is the correct goal and destination of your life, or whether you should be concerned about what happens after you die, whether you should be concerned about general issues of piety or rationality or abstract ideal forms — just what the correct orientation in life generally is. And all of that is wrapped up in this question of whether knowledge is possible. Because if you take the position, as the academic skeptics do, that knowledge is not possible, then you’re really not going to have a lot of credibility in arguing that any particular direction is the appropriate one.

As we’ve been discussing, the Stoics reacted strongly against that, because they are going to be defending virtue as the goal with even greater intensity than the academic skeptics are willing to do — to the extent that the skeptics are willing to advocate anything. And so the Stoics are taking the position, as Lucullus has been arguing in the section we’ve been reading, that knowledge is possible. And he’s going through a number of important arguments that give us significant information about the Epicurean point of view.

Last week we ended by reading Section 17. There are some continuing issues that we are going to have to double back and cover as we go further, especially the meaning of the Stoic view of assent, and of course the continuing issue of what is meant by a cataleptic impression. In Section 17, Lucullus said to the academic skeptics: you can quote Democritus that there are countless identical worlds that cannot be distinguished from each other, and you can use Democritus, if you like, to argue that nothing therefore can be known. But first of all, I’m not going to grant you that Democritus knows what he’s talking about in terms of his atomism, and I’m certainly not going to grant that Democritus is right in concluding that nothing is knowable.

Democritus was held in very high regard by Epicurus, but not necessarily in this aspect of his views, because Epicurus ended up taking some significantly different positions. Those positions allowed him to conclude, in contrast to Democritus, that knowledge certainly is possible — not to say that truth lies at the bottom of a dark well and end up as skeptical as Democritus apparently was. And of course I always say “apparently,” because our direct knowledge of Democritus is much less firm than we would like it to be, and we have to go on what other people quote from him.

But right here in 17 and 18, even though Epicurus himself is not the featured target of the discussion, there is an argument going on about physics in relation to canonics that overlaps exactly with what the Epicureans were addressing. And so seeing what the skeptics and the Stoics were arguing about between themselves is going to allow us to bring out exactly what the Epicurean position on this question was as well.

So that’s going to be my introduction for today. I’m now going to turn it over to Joshua to move us into 18. So Joshua, whenever you’re ready.

Joshua:

Lucullus in 17 gave something of a preview of what we’re going to be talking about today when he said this:

“What do you seek to gain by talking about twins? For it is granted that they are alike, and you might be content with that; but you try to make them out to be actually the same, and not merely alike; and that is quite impossible.”

So broadly speaking, we’re still talking about that same concept, and it’s been applied to twins, and to two eggs that can be distinguished from each other. And then we get to the ideas of Democritus — the innumerability of worlds, that there must be worlds which are identical to one another, and that we would expect, in an infinite cosmos, to find people on those worlds identical to each other. And this is Lucullus’s response to that:

“First of all I reply, that you are bringing me to the arguments of Democritus, with whom I do not agree. And I will the more readily refute them, on account of that doctrine which is laid down very clearly by the more refined natural philosophers, that everything has its own separate property.”

And let me interject to say that when he talks about everything having its own separate property, this is a Stoic idea. He continues:

“For grant that those ancient Servilii who were twins were as much alike as they are said to have been, do you think that that would have made them the same? They were not distinguished from one another out of doors, but they were at home. They were not distinguished from one another by strangers, but they were by their own family. Do we not see that this is frequently the case, that those people whom we should never have expected to be able to know from one another, we do by practice distinguish so easily that they do not appear to be even in the least alike?

“Here, however, you may struggle; I will not oppose you. Moreover, I will grant that that very wise man” — the wise Stoic man who is capable of true knowledge — “who is the subject of all this discussion, when things like one another come under his notice, in which he has not remarked any special character, will withhold his assent, and will never agree to any perception which is not of such a character as a false perception can never assume. But with respect to all other things he has a certain art by which he can distinguish what is true from what is false; and with respect to those similitudes he must apply the test of experience. As a mother distinguishes between twins by the constant practice of her eyes, so you too will distinguish when you have become accustomed to it.

“Do you not see that it has become a perfect proverb that one egg is like another? And yet we are told that at Delos (when it was a flourishing island) there were many people who used to keep large numbers of hens for the sake of profit; and that they, when they had looked upon an egg, could tell which hen had laid it. Nor does that fact make against our argument; for it is sufficient for us to be able to distinguish between the eggs.

“For it is impossible for one to assent to the proposition that this thing is that thing more, than by admitting that there is actually no difference at all between the two. For I have laid it down as a rule, to consider all perceptions true which are of such a character as those which are false cannot be. And from this I may not depart one finger’s breadth, as they say, lest I should throw everything into confusion. For not only the knowledge of what is true and false, but their whole nature too, will be destroyed if there is no difference between one and the other. And that must be very absurd which you sometimes are in the habit of saying, when perceptions are imprinted on the mind, that what you say is, not that there is no difference between the impressions, but only that there is none between certain appearances and forms which they assume. As if perceptions were not judged of by their appearance, which can deserve or obtain no credit if the mark by which we are to distinguish truth from falsehood be taken away.

“But that is a monstrous absurdity of yours, when you say that you follow what is probable when you are not hindered by anything from doing so. In the first place, how can you avoid being hindered, when what is false does not differ from what is true? Secondly, what judgment can be formed of what is true, when what is true is undistinguishable from what is false? From these facts there springs unavoidably epochē, that is to say, a suspension of assent: for which Arcesilas is more consistent, if at least the opinions which some people entertain of Carneades are correct. For if nothing can be perceived, as they both agree in thinking, then all assent is taken away. For what is so childish as to talk of approving of what is not known? But even yesterday we heard that Carneades was in the habit, at times, of descending to say that a wise man would be guided by opinion, that is to say, would do wrong. To me, indeed, it is not so certain that there is anything which can be comprehended, a question which I have now spent too much time in discussing, as that a wise man is never guided by opinion, that is to say, never assents to anything which is either false or unknown.

“There remains this other statement of theirs, that for the sake of discovering the truth, one ought to speak against every side, and in favour of every side. I wish then to see what they have discovered. We are not in the habit, says he, of showing that. What then is the object of all this mystery? Or why do you conceal your opinion as something discreditable? In order, says he, that those who hear us may be influenced by reason rather than led by authority. What if they are influenced by both? Would there be any harm in that? However, they do not conceal one of their theories, namely, that there is nothing which can be conceived. Is authority no hindrance to entertaining this opinion? It seems to me to be a great one. For who would ever have embraced so openly and undisguisedly such perverse and false principles, if there had not been such great richness of ideas and power of eloquence in Arcesilas, and, in a still greater degree, in Carneades?”

Cassius:

Okay, Joshua, thank you for reading Section 18 for us. There is a lot in this section that we’re going to be spending some time on, and in reading the whole thing, I begin to be more interested in some of the later comments than in what we intended to start off with in terms of Democritus. But I think many of the points here are going to be worth going into. So let’s go back to the beginning and talk a little further about this reference to Democritus versus “the more refined natural philosophers.”

The point we’re really homing in on here is whether there are, in fact, things that are identical to each other. Because the argument is that if there are things that are truly identical to each other, then there is no way to tell the difference between them. And if there’s no way to tell the difference between them, and to know whether something is identical to something else or not, then you’re going to be left confused and unable to determine whether you’re right or wrong in saying that this is one thing versus the other. This is the example of the twins — the Servilii twins, who were famous in that time period for being very difficult to tell apart.

So let’s talk about that for a few minutes. I know you’ve got some good insights into it, and we’ve done a little bit of looking into the background. Rackham cites the reference to “more refined natural philosophers” as a reference to the Stoics themselves, who considered themselves to be natural philosophers. They obviously reached a different conclusion than Epicurus about many different things, but they considered themselves to be materialists, and considered themselves to be looking to nature as their standard, just as Epicurus was attempting to do. So just as we have similarities and differences between the Stoics and the Epicureans on the nature of knowledge, we have similarities and differences between them on whether the universe itself is natural and material, and so forth.

And in order not to get confused between the two, but to see the very important implications of these differences, we’re going to have to spend a few minutes on this question of whether twins or leaves or diamonds or anything else in the world can truly be identical. And if there are in fact identical things, does that blast a hole in Epicurus’s view that it is possible to know the truth about something? Does the case of identical objects prove, as the skeptics would like to make it, that knowledge is impossible?

Before we started today, we took a few minutes to look back at a particular letter from Seneca which goes into some of these issues. Although it’s a slight tangent to talk too much about Seneca and the Stoics, I think this is important enough that we don’t want to just gloss over the implications of this question of identical things. So, Joshua, how would you like to tackle that?

Joshua:

Well, Seneca’s Letter 113 begins very similarly to Epicurus’s Letter to Pythocles. What they both have in common is that a student has written asking for clarification on an important point, and they both clear their desks and set to the problem of writing a response which explains the school’s position. Now, in the letter to Lucilius, the question is this: whether justice, courage, foresight, and the other virtues are living things. And Seneca says:

“By such niceties as this, my beloved Lucilius, we have made people think that we sharpen our wits on useless objects, and waste our leisure time in discussing what will be unprofitable. I shall, however, do as you ask, and shall set forth the subject as viewed by our school.”

And upon this point he launches into his discussion of the souls of men and the relationship between the soul and virtue — the idea that if virtue is a living thing, then virtue itself must possess virtue, as other living things do. And we get to a particular claim in this letter, which is what has connected it with what we’re talking about in Academic Questions. On the objection that if virtue is a living thing, then virtue itself possesses virtue, Seneca replies:

“Why, of course it possesses its own self. Just as the wise man does everything by reason of virtue, so virtue accomplishes everything by reason of itself. ‘In that case,’ say they, ‘all the arts also are living things, and all our thoughts and all that the mind comprehends. It therefore follows that many thousands of living things dwell in man’s tiny heart, and that each individual among us consists of, or at least contains, many living beings.’”

Of course, they didn’t know about microorganisms, Cassius, but that adds an interesting layer on top of what they’re talking about: when I point to someone and say I’m talking about them, there are potentially millions of organisms walking around in their shoes. And then Seneca replies:

“Are you gravelled for an answer to this remark? Each of these will be a living thing; but they will not be many separate living things. And why? I shall explain, if you will apply your subtlety and your concentration to my words. Each living thing must have a separate substance; but since all the living things mentioned above have a single soul, consequently they can be separate living things but without plurality. I myself am a living thing and a man; but you cannot say that there are two of me for that reason. And why? Because, if that were so, they would have to be two separate existences. This is what I mean: one would have to be sundered from the other so as to produce two. But whenever you have that which is manifold in one whole, it falls into the category of a single nature, and is therefore single.”

So being a living being, and being a man, and being a Stoic, and having hair or whatever — these are all attributes of Seneca. But Seneca is still just one thing.

Cassius:

Yes, I agree that that’s the point here. He’s going to go further, and there are some additional aspects of this, but to keep it wrapped into the major category: we’re still talking about whether knowledge is possible, and whether the possibility of things being identical to each other would make knowledge impossible — because you would never be able to tell the difference between something and something identical to it. We’re going to see how Seneca brings that into an almost theological argument before we finish here.

But Joshua, continue where you are, because we haven’t gotten into this part of it yet. Seneca is going to begin to sort of apologize for talking about all this: this is all just so impractical; we just need to talk about something else. But really, the question we’re discussing is important and does not deserve to be deflected. And so we’re going to stick with it like a laser, and before we finish, bring it all back to this question of whether identical things are possible or not, and if they are possible, whether that blasts the possibility of knowledge. For that reason, Seneca is going to conclude that truly identical things are impossible. We’ll come back and talk about Epicurus’s position, but Joshua, you continue.

Joshua:

And it will benefit us to go into some detail here. Seneca continues by saying:

“My soul is a living thing, and so am I; but we are not two separate persons. And why? Because the soul is part of myself. It will only be reckoned as a definite thing in itself when it shall exist by itself; but as long as it shall be part of another, it cannot be regarded as different. And why again? I will tell you: it is because that which is different must be personal and peculiar to itself, a whole, and complete within itself.”

Now, Seneca disagrees with other Stoics on this question, and he talks about that a little in the letter. He says here:

“I myself have gone on record as being of a different opinion; for if one adopts this belief, not only the virtues will be living things, but so also will their contrary vices and the emotions, like wrath, fear, grief, and suspicion. Nay, the argument will carry us still further — all opinions and all thoughts will be living things. This is by no means admissible; since anything that man does is not necessarily the man himself.”

Seneca does go on to talk about virtues, emotions, vices, and all of these things as living beings. But again it comes back to the question: are they many countless things sojourning in this one soul? And no, he says, is the answer, because they are all attached to the one being, parts and members of a single whole. And then he brings up the chimera: a being with multiple heads — is it multiple different things?

The interesting part for us comes slightly later, when he says this:

“Every living thing exists as it began until death; a man, until he dies, is a man; a horse is a horse, a dog a dog. They cannot change into anything else. Now let us grant that justice — which is defined as ‘a soul in a certain attitude’ — is a living thing. Let us suppose this to be so. Then bravery also is alive, being ‘a soul in a certain attitude.’”

And in 291 he establishes this rule:

“Again, no living thing is part of another living thing. … The Creator has set himself the task of making unlike and unequal things that are different; but all the virtues, as your argument states, are equal. Therefore they are not living things.”

He does continue to talk about virtues in this way throughout the rest of the letter. But Cassius, do you have a particular point you want to jump in on here? Because remember, we’re not talking about virtues over in Academic Questions. We’re talking about whether it is possible for there to be two things which are truly and genuinely identical, in a way that no person or combination of persons, and no knowledge or instrument, would allow anyone to distinguish between them.

Cassius:

Yes, Joshua, let me emphasize what you were just reading, beginning around Section 15 as marked in the Wikisource text that I’ll link today. He says:

“Again, no living thing is part of another living thing. But justice is a part of the soul. Therefore justice is not a living thing.”

Stop there for just a second, and I’m sure this is just going to display my lack of understanding. To me, when he says “living thing,” it sounds like he’s getting into what Epicurus addresses in terms of whether justice is a thing in itself — whether it has its own independent existence. Now, he’s using the phrase “living thing” as it’s translated here, so maybe there’s some difference. But at least in what we’ve focused on in the past, the question has been whether justice is a thing in itself. And then it continues:

“It looks as if I were wasting time over something that is an acknowledged fact; for one ought to decry such a topic rather than debate it. And no two living things are equal. Consider the bodies of all beings; every one has its particular color, shape, and size.”

And here’s an important point, because we always have to be concerned about where the Stoics are really going and what’s really motivating them. Listen to this next sentence, indicated as 16:

“And among the other reasons for marvelling at the genius of the Divine Creator is, I believe, this — that amid all this abundance there is no repetition; even seemingly similar things are, on comparison, unlike. God has created all the great number of leaves that we behold: each, however, is stamped with its special pattern. All the many animals: none resembles another in size — always some difference! The Creator has set himself the task of making unlike and unequal things that are different; but all the virtues, as your argument states, are equal. Therefore they are not living things.”

Okay, that’s the end of the quote. I’m going to suggest that we need to look past this example of the virtues as living things, and look at what I think is motivating Seneca and what he thinks is essential: that God as the creator has made everything unique and stamped it with its special pattern. And I have to think that the Stoics are linking the cataleptic impression to this idea that everything is unique. When he talks about all the animals differing from one another in size — what’s the example we like to use today? That no snowflake is the same as any other; that they’re all unique. As I say this, I’m not sure exactly where science comes down right now, but I think that type of argument is where Seneca is going. And I don’t think it is scientifically proven that all snowflakes are unique and different from each other.

And Joshua, as we come back to where Epicurus’s position is: the Stoics are nailing down the position that no two things are absolutely identical with each other. Democritus apparently took the position that there are an infinite number of worlds that are exactly the same as ours. Well, the Stoics don’t like that. They want everything to be unique and stamped with its special pattern. “Stamping” is a verb I think we also see in On the Nature of the Gods, where Velleius, the Epicurean, criticizes the idea of a divine creator manufacturing things as if stamping them out of a die, each with a special pattern. We’ll be discussing this as we go further.

But I think Epicurus is saying that there’s an infinite number of worlds both like ours and unlike ours. And so Epicurus is going to differ from the Stoics and say that there are not only some, but an infinite number, of worlds or men that are absolutely identical in atomic structure and composition with others. So Epicurus is not going to say, “I can tell things are different because everything is stamped with its unique pattern.” I think we’re going to find that Epicurus says instead that we can distinguish things from each other using the sensations, anticipations, and feelings in our own experience. That does not necessarily mean there are not, in fact, identical objects.

And the way we end up reconciling that, as I see it, speaking today on October 4th of 2026, is that Epicurus is referring back to the idea that everything that appears to us is, in fact, real — that our reality is determined for us through the sensations, anticipations, and feelings. We are not, as Epicureans, taking the position that there is a central, arbitrary creator who has stamped everything with a unique mark that we can use to say that this is different from that. We are going to have to rely on our sensations, anticipations, and feelings. But in our reality, from our perspective, at our level of existence, that method is going to be sufficient to distinguish one thing from another. And we are not going to be hindered by that fact from taking the position that knowledge is possible.

The skeptics are trying to say: you’ve admitted that there are certain things that are identical; that means you cannot really tell one thing from another; therefore it’s always possible that your conclusion is false. And the Stoics are wrestling with that. As we saw before we came over to Seneca, the Stoics are saying that nothing is truer than that the wise man will never go by opinion, and that he’ll never assent to anything which could possibly be false.

We’ll have to continue on that point as we explore the details more directly. But the point is going to be that Epicurus agrees to an extent: if we don’t have sufficient information, we are not going to take a position. We’re going to “wait,” in the Epicurean terminology, before we take a position that something is true or false. But we are not going to insist on the experience of the wise man, whom the Stoics admit is as rare as the phoenix. We’re not going to admit that only the wise man is able to make a judgment and to say that he has knowledge of something. We’re going to take the position that knowledge is based on a realistic perspective brought to us by the sensations, anticipations, and feelings, and that those faculties can be used appropriately to take the position that some things are known and some things are not known, and that some things are true and some things are false.

We’re not going down the road the Stoics are attempting to go, saying that there’s a divine creator who has stamped everything with its own unique mark — that it may be impossible for us to tell whether one diamond or one egg is exactly the same as another, but in the case of eggs, there are people who spend their lives on farms dealing with chickens and get really good at telling which chicken laid a particular egg, and so that’s an indication to us that God has stamped every egg with its own unique mark, and through experience and training we can eventually rise to the level of the phoenix, be the wise man, and actually know what is true. Epicurus is not going to take that path. He’s going to say that there’s a realistic definition of knowledge, a realistic definition of true and false, in which, through the sensations, anticipations, and feelings, we can reliably take a position on what is true versus what is false.

Joshua:

You know, I can understand why this would be an attractive view of nature — that nature never produces exact copies of anything. You know what it reminds me of? The passage in Shakespeare’s Antony and Cleopatra, in reference to Cleopatra: “Age cannot wither her, nor custom stale her infinite variety.”

In an Epicurean cosmos, the universe is made of atoms, and there are an infinite number of atoms, and there are an innumerable number of different kinds of atoms. It seems to me that there should be exact duplicates if we’re talking about an innumerable number of different kinds — or else I’m curious about how you categorize a kind.

It’s true that Epicurus and Lucretius do talk about important instances where things appear very similar to us, and yet are not. Lucretius has a very moving passage in Book Two, around line 352, about the calf taken away to be slaughtered and sacrificed at the smoking altars in dedication to the gods. In the Cyril Bailey translation it says:

“But the mother bereft, wandering over the green glades, seeks on the ground for the footprints marked by the cloven hoofs, scanning every spot with her eyes, if only she might anywhere catch sight of her lost young: and stopping fills the leafy grove with her lament: again and again she comes back to the stall, stabbed to the heart with yearning for her calf. Nor can the tender willows and the grass, refreshed with dew, and the loved streams, gliding level with their banks, bring gladness to her mind and turn aside the sudden pang of care; nor yet can the shapes of other calves among the glad pastures turn her mind to new thoughts or ease it of its care: so eagerly does she seek in vain for something she knows as her own.”

Cassius:

Joshua, let me jump in on that example before you go forward with it. I don’t know what I thought that passage was talking about in the past, but now it seems to me to be aimed directly at what we’re talking about right now. There are an innumerable — in fact infinite — number of identical atoms. That does not mean every atom is identical, because I think it’s clear Epicurus is saying there’s an innumerable number of different kinds of atoms. But let’s hammer this point down, and stand to be corrected next week and walk it back if it turns out to be wrong: in Epicurean philosophy, there are atoms that are identical with each other. And if there are atoms identical with each other, that leads to the conclusion that there are an infinite number of identical worlds, because you’ve got identical atoms to work with.

So, linking it to your story of the mother cow and her calf, we’ve got to understand both positions: there are identical things in the universe, but the mother cow is still, despite these identical atoms, able to tell her calf from another. And I would relate this to the position I was arguing a few minutes ago, that the sensations, anticipations, and feelings of that cow are sufficient to allow her to recognize her own calf. At the same time, there are innumerable identical atoms. So in some other world, in some other galaxy, there can be another identical calf, but that does not prevent this mother cow from knowing her own calf. She’s not concerned about the skeptics saying that there are things out there that are identical, and that therefore she may be mistaken. She’s living her life knowing her own calf, based on what nature has given her to understand her calves and distinguish them from others.

So I’m sorry to interrupt there, but I’ve always thought this was a very nice passage about the emotion involved in losing your calf to a sacrifice to the gods. And I think it is an important part of what’s being discussed here. Clearly there is a major issue involved in whether there are identical things out there — and if there are identical things, then it’s impossible for you to know, mother cow, whether that’s your calf or not, because there’s an infinite number of calves out there identical to yours. That’s what Democritus says. So how do you know anything, mother cow? Why don’t you just take the position, “Well, this calf seems to me to be mine, but it might not be mine; I might be mistaken”? I think that’s where all this is going, and why it’s so important.

And I’ll express a little further irritation at Seneca here, because Seneca kind of pooh-poohs this whole question and sort of apologizes that it’s really a waste of time: why are we talking about this? Let’s just live prudently, let’s just live with justice, because all I really want to know is what it means to be brave and how to be brave — that’s all that really matters. Well, he’s skirting the issue the skeptics have raised. The skeptics have to be met and addressed, so that their argument can be seen to be what Lucullus has called it here: a monstrous absurdity.

Joshua:

Yeah, and it’s important to recognize that there are still limits in nature, and that there are other rules — other perceived rules in Epicurean physics — that seem to bump up against this same idea, or at the very least are adjacent to it. There’s the idea of isonomia: that nature never produces just one thing of a kind. If you find one thing in nature — you’re never going to find just one otter, for example. There has to be a group of otters, a breeding population of otters, and so on.

And likewise, especially in Lucretius, we get the idea that there are clear distinctions between things, and that every living thing is traceable back to a particular source. Most obviously with fruit trees: apples don’t spring forth on the trees that normally produce oranges. Apples have to grow on trees that come from saplings or seeds or rootstock that produce apples. You can’t cross that boundary in nature.

Immediately after talking about the mother cow searching for her calf, Lucretius says:

“Take any kind of corn, you will not find that every grain is like its fellows, each in its several kind, but that there runs through all some difference between their forms.”

This would seem to be saying the exact opposite of what we’re saying, Cassius — that there are things in nature that are atomically identical. In like manner, he says:

“We see the race of shells painting the lap of earth, where with gentle waves the sea beats on the thirsty sand of the winding shore. Wherefore again and again in the same way it must needs be, since the first-beginnings of things are made by nature and not fashioned by hand to the fixed form of one pattern, that some of them fly about with shapes unlike one another.”

And then he talks about fire, and he says that the atoms of light must be smaller than other atoms. So it’s true that some atoms of a particular class are identical to each other, I would think. It’s also true that you can tell the difference between the effects produced by atoms of different classes.

Cassius:

Yeah, Joshua, I think we’re in agreement, and I think what we’re saying is ultimately reconcilable with Lucretius here, because the ultimate point is that some atoms are identical with others and some atoms are not identical with others. We don’t ever see or touch atoms directly. So we have to keep in mind that atoms can be the same or they can be different. What we’re most concerned about is living happily, in this world and at our level of experience. And in our world of experience as well, there can be things that are identical, but in most cases they’re not identical. In most cases there are significant differences, because things are made of atoms, and it takes billions of atoms coming together to produce anything at our level. So in most cases, things are not going to be identical.

But why are they not identical, and how do we tell the difference? We’ve got a lot more that we need to say about this, but it’s not because God stamped them out in a particular pattern, or marked them in a particular way, so that they are all unique. We’ve got to be able to navigate between the two possibilities, that something is unique and that something is identical. And the existence of things that are unique does not eliminate the possibility that there are things that are identical.

I think you pulled a great example in referencing isonomia — this idea that nature never makes only one thing of a kind. That’s a perfect point in Lucretius which illustrates that nature never makes only a single thing of a kind. It’s going to lead us to deal with the fact that there are things that are very close to each other, and things that are not at all close to each other, but there are also things at times — maybe rarely — that are identical. And so we have to be able to navigate knowing that both possibilities exist: that we may be looking at something that is identical, or we may be looking at something that is unique. But God isn’t going to tell us by stamping it for us, so that we can learn to read God’s markings and see whether something is the same or not. We’re going to have to be able, like the mother cow, to distinguish our own calf from other calves.

A skeptic may look at that cow and say, “Don’t worry, mother cow, there’s another one out there that’s exactly identical, and you’re not sure that the one you lost was yours anyway.” And I think Epicurus is saying that’s not the way cows think, and it’s not the way we should think either, because nature has given us sensations, anticipations, and feelings. We, at our level of existence, have things that we identify as the same, and we also have things that we identify as unique. And we’re able to deal with this issue in a way that does not require us to resort to a god who stamps out things with a particular pattern. There are patterns, and there are things that are stamped — we create them ourselves — but the absence of a divine creator stamping out marks does not mean that knowledge is impossible.

Joshua, we’re eventually going to have to bring today’s episode to a conclusion, and we’re probably in the middle of this discussion and will be able to refine it as we go forward. But I think we’re hitting on some really important issues that need additional development, and that I would not even have recognized existed in the past. Now I think it’s clear, when we see what Lucretius is talking about and overlay it with what Cicero is saying here. And of course Cicero is our source for information about isonomia, through Velleius. We’ve got these comments from Lucretius that never seemed very important standing on their own. But when you realize that you’ve got to have a theory of knowledge, it becomes easier to see that they’re essential. They’re not something to be skipped over as raw science with no implications. They are something we have to have a working ability to deal with, or else we get upended by the skeptics and led down the path of thinking that no knowledge about anything is possible.

Joshua:

These are fascinating questions, Cassius, and no doubt we profit from exploring them, especially in light of things in Lucretius that become ever clearer the more we branch out into ancient philosophy and see what the conversations of the ancient world centered around. We’re going to keep all of this in mind — identical twins, and whether two different things can be truly identical in nature — as we go forward.

It looks like next week we’re going to get into the second paragraph of 18, focusing on the response to all of this from the archetypal Stoic wise man, who, with his ability to withhold his assent, “will never agree to any perception which is not of such a character as a false perception can never assume.” And I have to wonder, Cassius, whether this idea of withholding assent — which the Wikipedia page for katalepsis defines as “adherence to the truth thus understood” — amounts to anything more than a toddler sticking his fingers in his ears and shouting “la la la”: I don’t want to agree that I’ve perceived what I’ve perceived. But all of that is coming up.

Cassius:

I think you’re exactly right, Joshua. We’re going to have to develop some additional analogies, because all of us are familiar with being taught in church when we were younger that every hair of your head is numbered — all of these things about how God knows how one sparrow differs from another, and so forth. And it becomes increasingly clear that the Stoics are attempting to say that somehow the wise man is never going to make a mistake and confuse what is true with what is false. But you can’t just stop there and say that somehow he’s going to know this — that maybe, if he spends a whole lifetime trying to climb the mountain of virtue, he’ll eventually reach the level of the phoenix and be the rare person who knows what the truth is. That is a ridiculous way of approaching things.

And it deserves the abuse that the Stoics are applying here to the skeptics, when they say that it is a monstrous absurdity to claim that nothing can be known. But I think we could counter by saying that it’s also a monstrous absurdity to say that knowledge of true and false has to depend on some supernatural creator having stamped everything with his own seal of approval, which we need to come into contact with through meditation and prayer and so forth.

Well, again, as you’ve indicated, these are deep issues that we’re going to be diving into further as we proceed next week in Section 18. So we’ll stop there for today. We invite everyone to drop by the EpicureanFriends forum and let us know if you have any comments or questions on these or our other discussions about Epicurus. Thanks for your time today. We’ll be back again soon. See you then. Bye.