Episode 242 - Is Truth A Matter Of Logic?
Date: 09/26/24
Link: https://www.epicureanfriends.com/thread/4052-episode-247-cicero-s-otnotg-22-cotta-continues-to-attack-the-epicurean-view-that/
Summary
Section titled “Summary”This episode takes up the question “Is Truth a Matter of Logic?” prompted by Cotta’s attack on Epicurus in Sections 24–25 of Cicero’s On the Nature of the Gods. Cotta charges Epicurus with inventing expedients — specifically the atomic swerve and the refusal to accept the disjunctive proposition “Epicurus will be alive or dead tomorrow” — whenever logical necessity leads somewhere Epicurus dislikes. The discussion contrasts rationalism (a priori reasoning from axioms, exemplified by Plato and St. Anselm’s ontological argument) against empiricism (deriving knowledge from sensation and experience, exemplified by Epicurus and Darwin on the evolution of the eye). Eratosthenes of Cyrene is cited as a rare Greek who applied geometry to measure nature. St. Anselm’s ontological argument from the Proslogion is laid out and then countered with an alternative syllogism yielding the opposite conclusion; David Hume’s response is quoted (“nothing is demonstrable unless the contrary implies a contradiction”). Democritus’s extreme skepticism (“truth lies at the bottom of the well”) is contrasted with Epicurus’s practical epistemology. The episode covers Cotta’s critique of Velleius’s “quasi-body” and “quasi-blood” language about the gods, Lucretius Book 4 on trusting the senses despite apparent contradictions (the square tower appearing round from a distance), and David Sedley’s article on Epicurus’s refutation of determinism. Preview: Section 26 of On the Nature of the Gods next week.
Transcript
Section titled “Transcript”Cassius: Welcome to Episode 242 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 have a thread to discuss this and each of our podcast episodes.
Today we’re continuing in Cicero’s On the Nature of the Gods. We’re now in the section where Cotta the Academic skeptic is responding to Velleius’s presentation of the Epicurean point of view. Last week we spent most of the episode talking about the parallel in the way that Torquatus presented Epicurus’s definition of the good — as something which all philosophers agree is a standard by which we judge everything else, but we don’t judge the standard itself by anything else — and we compared that to Velleius’s presentation of Epicurus’s view of the gods as being living beings which are blessed and imperishable. In both cases, we were setting forth what we might consider to be a definition or an explanation, or a pointing to a particular concept, so that we could then begin the discussion in detail as we go forward.
In Section 24, Cotta is going to begin attacking Velleius’s position, alleging that it is not true. And he is using the word “true” in “truth” in several different instances. We’re going to want to go back and examine what he’s saying and what we should ourselves take away from any kind of discussion of truth.
To set the stage for that, just briefly: probably what’s thought to be one of the most standard definitions of truth that everybody goes back to when you start talking philosophically about truth is what’s called the correspondence theory of truth. I’m looking at a page from the Stanford Dictionary of Philosophy and it says that the correspondence theory of truth is often traced back to Aristotle’s well-known definition of truth in his Metaphysics, where he says: “To say of what is that it is not, or of what is not that it is, is false. Well, to say of what is that it is, and of what is not that it is not, is true.” Now that’s classical Aristotelian word-play there, and certainly when you dissect it, it makes sense. But it comes down to a very practical question of whether what you’re saying — whether what your opinion of something is — corresponds to what is existing in reality. That’s where the word “correspondence” comes in. What we’re talking about in discussing truth is to describe accurately in words something that we can say corresponds with what is objectively real, out there beyond us and beyond our words.
This article — which I’ll link to in the show notes — talks about different ways in which Plato and Aristotle attack that problem. Of course, that’s what eventually gets us into all the different rabbit holes we can go down in terms of Plato’s analogy of the cave, in terms of whether you can ever see truth, whether all you’re doing is seeing reflections or shadows on a wall, whether the senses are capable of obtaining truth or not — which is where Plato went off and said they’re not, and you must use logic in order to get to the truth. All sorts of questions like that.
But from a more practical point of view, we just need to be sure that we have a working definition of truth and true-or-false. And it’s going to end up being something like saying that our words paint a picture that corresponds with reality. Now, we have a couple of references in Diogenes Laertius that are worth mentioning, and those bring home to us that Epicurus is focusing on words that describe reality to us — and not words focused on abstractions that have no relationship to us.
After talking to us about how Epicurus rejects logic as misleading and telling us that the test of truth is the sensations and the preconceptions and the feelings, Diogenes Laertius records: “Nor is there anything which can refute the sensations. And here’s the important part for our discussion today: the fact of a perception confirms the truth of the sensation. And seeing and hearing are as much facts as feeling pain. From this it follows that as regards the imperceptible, we must draw inferences from phenomena — those things that we were observing. For all thoughts have their origin in sensations by means of coincidence and analogy and similarity and combination, reason too contributing something. And the visions of the insane and those in dreams are true, for they cause movement, and that which does not exist cannot cause movement.”
Now that last sentence in particular I think is helpful, because it always shocks people to hear that the visions of the insane and the visions of things we see in dreams are “true.” Because that’s the use of the word “true” that we’re not most commonly using. We’re commonly using “true” to say that what you’re talking about does actually exist in objective reality — you can go out and touch it and so forth. But what Epicurus is saying is that when you’re asleep and have a dream, or when you’re insane and you have a vision, you are still perceiving things that are changing you, that are motivating you to do something. Whether you start awake because of the dream you’re having, or if you’re insane and you think you’re seeing something, you’re reacting to something that’s going on somewhere. In many cases what’s going on somewhere is something that’s going on inside your mind. But what Epicurus is focusing on is that you should consider those things to be true or real that actually affect you. In Epicurus’s analysis, anything that causes movement within you is something that exists as true or real, at least in that sense.
Continuing on, in section 34 Diogenes Laertius records: “Opinion they also call ‘supposition’ and say that it may be true or false. If it is confirmed or not contradicted, it is true; if it is not confirmed or is contradicted, it is false. For this reason they introduced the notion of the ‘problem awaiting confirmation,’ for example, waiting to come near the tower and see how it looks to the near view.”
There’s also a long discussion of the same issue in Book 4 of Lucretius, where he is talking about the images. But where we are in the text in Section 24 is that Cotta is challenging Velleius’s position by saying: “You, Velleius, are committed to this idea of atoms being the basis of everything. But what I’m telling you is that atoms are absurd. Atoms were absurd when Democritus stated them. They were absurd when Leucippus stated them, and you’ve now brought down to our times this same absurdity that cannot be true.” And Cotta says: “But where is truth?”
“The truth cannot be in the atoms, because whatever is made of atoms had to have a beginning. And if the gods are made of atoms, then they must have had a beginning — and that’s something that is absurd, that a god had a beginning.” And before I turn it over to Joshua to comment, Cotta goes further and says: what you’re saying about the gods makes no sense, and in fact:
“It is a frequent practice among you, when you assert anything that has no resemblance to truth and wish to avoid reprehension, to advance something else which is absolutely and utterly impossible, in order that it may seem to your adversaries better to grant the point which had been such a matter of doubt than to keep on continuously contradicting you on every point. Like Epicurus — when he found that if his atoms were allowed to descend by their own weight, our actions could not be in our own power because their motions would be certain and necessary — he invented an expedient which escaped even Democritus to avoid necessity. He says that when the atoms descend by their own weight and gravity, they move a little obliquely. Surely to make such an assertion as this is what one ought to be more ashamed of than the acknowledging ourselves unable to defend the proposition.
“His practice is the same against the logicians, who say that in all propositions in which yes or no is required, one of them must be true. Epicurus was afraid that if this were granted in such a proposition as ‘Epicurus will be alive or dead tomorrow,’ either one or the other must necessarily be admitted. Therefore, he absolutely denied the necessity of yes or no. Can anything show stupidity in a greater degree? Zeno, being pressed by Arcesilaus, who pronounced all things to be false which were perceived by the senses, said that some things were false, but not all. Epicurus was afraid that if any one thing seen should be false, nothing could be true, and therefore he asserted all the senses to be infallible directors of truth. Nothing can be more rash than this, for by endeavoring to repel a light stroke, he receives a heavy blow.”
We’ll stop there in the reading. But basically what we’re setting up for today’s discussion is that Cotta is alleging that Epicurus is playing fast and loose with truth — that when he feels like he has run into an obstacle in one location (such as atoms falling downward leading to necessity, which he doesn’t want), he just revises his understanding of the truth rather than providing an explanation which makes sense logically. And so what we’ve basically done here in today’s opening is set up this dilemma: do we derive truth through logic and syllogistic reasoning? Or do we derive truth through practical observation through the senses? Which makes the most sense? Which best conforms to a practical definition of truth? Which version of truth is the most useful to us, and at the same time the most correct?
Joshua: I’m going to begin, Cassius, by drawing out that distinction you were making there at the end, by highlighting the difference between two approaches to understanding things in nature. And these two approaches are very much present in the ancient world. They are the subject of philosophical disputes in and before the time of Epicurus. And to some extent it’s these two positions that still present a huge component of the arguments and debates that we have today.
So the two modes of inquiry — you might say, when you’re looking into things in nature — are rationalism, of the kind typified by Plato, for example, and empiricism. We’ll call Epicurus an empiricist. I know this isn’t strictly true necessarily, but for the purposes of comparison here I think it’s helpful.
So the rationalist approach holds that people can gain knowledge of the truth through the application of reason and logic. And I think of these scholastic, medieval monks and so forth writing books. They’re coming up with a priori logical arguments for the existence of God. It doesn’t necessarily occur to them that if they want to understand some of this stuff, they should go examine things in nature, form hypotheses, subject them to experiments. Instead, we’re going to start with a core set of axioms and we’re going to use logic to develop our system. And never at any point are we going to take the conclusion that we get from this process and subject that to experimentation. And on the subject of the gods, this is not necessarily possible to subject to experiment.
The focus on geometry in the ancient world — and Epicurus’s impatience with the level of attention and study given to geometry in the ancient world, exemplified by the quote that was said to be over Plato’s Academy: “Let no one ignorant of geometry enter here” — this emphasis on geometry is an emphasis on education in the rationalist style: start with a set of axioms and definitions. If you can define what a point is, if you can define what a line is, with just a few basic axioms, you can build up this whole system. And of course in geometry, which is a theoretical versus practical field, you can establish things with a very high level of certainty. But the question comes: how do you apply that to the world that we’re actually living in?
Empiricism very much has its focus on the world that we’re actually living in, because empiricism attempts to derive knowledge of the truth from experience, from sensation, from experimentation. And so we’re not going to cloister ourselves in our studies and just work things out using mathematics or using logic or using reason, starting not with observation but starting with basic assumption. This approach, while it may be internally consistent, can lead you down a false path because the further you get from the ability to check your results in nature, the more in danger you are of going very wide of the mark. Whereas for empiricism, your approach is to constantly check your results by reference to things in nature.
So in the case of geometry, for example, you did have Eratosthenes of Cyrene in the ancient world — a figure at the library of Alexandria, a student of geometry — but he also had this question of: how can we use geometry not just in this pure theoretical Euclidean space in our minds? How can we apply this in nature? And he performed this well-known experiment to actually measure the circumference of the earth using geometry, and the results were quite spectacular. But this kind of thing is quite rare among the Greeks. They just weren’t interested in the application of theory to the facts of nature. So that, to me, is the first place to start drawing this distinction between the rationalist approach versus the empiricist approach.
The other place to start is with Democritus, who gets a mention here by Cotta. Cotta says — as you quoted — “It is a frequent practice among you when you assert anything that has no resemblance to truth and wish to avoid reprehension, to advance something else which is absolutely and utterly impossible in order that it may seem to your adversaries better to grant you that point… like Epicurus, who when he found that if his atoms were allowed to descend by their own weight our actions could not be in our own power, invented an expedient which even escaped Democritus to avoid necessity.”
The works of Democritus don’t survive except in a very fragmentary form. We have a handful of quotations. And if you go to the Wikiquote page on Democritus, there’s a section called “The Sourcebook in Ancient Philosophy 1907” and under that you have the fragments. And almost every single one of them deals with the question of truth. Democritus says: “Man should know from this rule that he has cut off from the truth.” “This argument too shows that in truth we know nothing about anything, but every man shares the generally prevailing opinion.” “Yet it will be obvious that it is difficult to really know of what sort each thing is.” “Now that we do not really know of what sort each thing is or is not has often been shown.” And then probably the most famous one: “Of truth, we know nothing, for truth lies at the bottom of the well.”
And finally there’s one that I’ve mentioned many times before. Democritus says: “By convention sweet, by convention bitter, by convention hot, by convention cold, by convention color — but in reality there are only atoms and void.” That only the atoms and the void exist. Everything else is only thought to exist.
So Democritus, far more than Epicurus, is prepared to take the kind of skeptical line that Cotta himself takes when he says “of truth, we know nothing.” Cotta would be very happy, I think, with that. There is ongoing debate in Epicurean circles as to how much of Epicurus’s philosophy was developed in service of his ethics. And Cotta puts his finger on the main point here, which is: Epicurus thought determinism was abhorrent. So how does he deal with this question of determinism? And from Cotta’s point of view, Epicurus just invents, ad hoc, a new law of nature in order to circumvent or evade this problem of determinism. So I think that really gives us an interesting test case.
Cassius: Let me jump in there for a second, Joshua, because that’s a great example. Cotta and the determinists are accusing Epicurus of inventing something to explain what he wants the result to be. But Epicurus’s response to that would be: “I’m not the one who’s inventing something to explain nonsense. I’m the one who’s looking at reality the way it is, and I see that I am not determined. And that means that something’s going on with those atoms that allows me not to be determined. One possibility is that they swerve, and that ultimately translates into the ability of my mind to determine a particular path of its own. But whatever the explanation is, I’m not going to lash myself to the mast of some logical position when it contradicts what I can see reality to be myself.”
I would use some analogies there. We hear lots of examples where people are following their cell phone navigation system when they’re driving — especially at night or in bad weather. They’re following the navigation and it says “turn here,” because it thinks there’s some bridge over some body of water. But the bridge for some reason is not there. And perhaps you’ll be able to see that before you get to it and avoid falling into the river. But the bottom line is: you do not follow a navigation system when you can see that ahead of you is a cliff that you are about to drive over. If you’re driving a Tesla today and you have automatic-driving abilities, and it wants to swerve in a particular direction, and you see that there’s a bulldozer in that direction and for some reason it’s driving you straight into it — you’d better grab the wheel and override the automatic driving, or you’re going to be dead.
There are examples after examples of things like that. Reality is what you’re ultimately concerned about. You’re not ultimately concerned about consistency with some logical system that you believe is the truth. There’s a famous saying that people argue about — whether Winston Churchill said it or John Maynard Keynes is apparently more likely the candidate — but it goes, as part of a conversation, where Keynes says: “When the facts change, I change my opinion. What do you do, sir?” And that’s the bottom line. You can come at something with a preconceived logical expectation, but when reality hits you in the face and it’s not in accord with what you expect it to be logically, you go with reality. You don’t go with some logical faith or belief that the logic is going to save you from the obvious hazard.
So I think that’s one of the ways we can see where this is going. Because when Cotta accuses Epicurus of inventing an expedient, he’s attempting to ridicule — he’s attempting to say: “You don’t know, Epicurus, what you’re talking about with your swerve of the atoms. You’re just inventing this, and that is absurd and ridiculous and something that not even a child should be willing to take such a position on.” But what Epicurus is saying in response to that is: I’m taking that position because that’s the reality of the situation, and that means that our logical framework needs to be adjusted. Reality isn’t going to adjust itself. The bulldozer or the lake that’s in front of our car is not going to adjust itself. We have to adjust for reality, not expect reality to adjust for us.
Joshua: Yeah, I think it’s an important part of this empiricist approach. You’re not starting with first principles and building up a system. Instead you are observing effects that exist in nature and trying to work your way back to the cause. And there’s an excellent quote on this from Charles Darwin. He’s dealing with the problem: “I’ve developed this theory of understanding speciation — how things came to be the way they are.” He’s looking at the effect — which is, “I went to the Galapagos and I observed that some of the finches on this island have especially long beaks and over here they’re different” — but what happens when I apply this to a system that appears to be so complicated that my explanation may not even answer to how this effect came to be produced?
And what Darwin says is this, speaking of the complexity of the eye: “To suppose that the eye, with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, seems, I freely confess, absurd in the highest degree.” Now, if you are a young-earth creationist, that’s where you stop the quote — and I see this quite a lot on the internet, that “even Darwin admitted he was wrong here.” But Darwin didn’t stop there. He continues and says this:
“When it was first said that the sun stood still and the world turned around, the common sense of mankind declared the doctrine false. But the old saying of Vox Populi Vox Dei, as every philosopher knows, cannot be trusted in science. Reason tells me” — and again, he’s not reasoning from a set of axioms here; he’s taking the effect and working his way back to the cause — “Reason tells me that if numerous gradations from a simple and imperfect eye to one complex and perfect can be shown to exist, each grade being useful to its possessor, as is certainly the case; if further the eye ever varies, and the variations be inherited, as is likewise certainly the case; and if such variations should be useful to any animal under the changing conditions of life; then the difficulty of believing that a perfect and complex eye could be formed by natural selection, though insuperable by our imagination, should not be considered as subversive of the theory.”
Now this passage contains its own problems, particularly when Charles Darwin says “when it was first said that the sun stood still and the world turned around, the common sense of mankind declared the doctrine false.” Part of the process is that the accumulation of knowledge is gradual, and you can’t expect to develop it all at once. So what we know now is that not only would we not say that the sun stands still and the earth orbits around it — we would say that actually the sun and the earth are both in motion on their own terms. You could say of the earth and the moon, for example, that in a sense the moon orbits around the earth — that’s not exactly false — but maybe it’s more true to say that the earth and the moon both orbit around their common center of gravity, which is partway between the center of the earth and the center of the moon. Because what Albert Einstein discovered in nature was: there is no absolute frame of reference. If you hit a golf ball, from the point of view of the golf ball, the golf ball is sitting still and the world is moving away from it. And again, that’s not exactly a wrong way to put it.
So when you get into celestial phenomena — as Epicurus does in the Letter to Pythocles — things become more tentative. But it doesn’t mean that we can’t gain knowledge about facts, that we can’t know what is true and what is not true. We still have this capacity. And this is actually, I think, very important for Epicurus: that things can be known.
Cassius: Yeah, I agree. It’s super important to Epicurus. And these things that we’re discussing today are particularly interesting to me because here we think we’re talking about On the Nature of the Gods, and some people are going to say, “Well, I don’t want to hear any discussion about religion.” But what we’re having to deal with in dealing with these questions is basic philosophy that applies to virtually anything that we’re talking about — all the way through Darwin, or any other way that we’re going to get at these basic philosophical issues.
Let’s go ahead, and in that context tackle the second of Cotta’s challenges here. Because the first example that Cotta has given is: “Epicurus said that the atoms just fall straight down due to their weight, but then when he didn’t like that result, he changed his position and said that they swerve a little bit.” And so that’s one argument. Here’s a second argument that we also mention fairly regularly — one that has nothing to do with gods in particular, but is another example of this issue of logical consistency. Here’s the quote again:
“Epicurus’s practice is the same against the logicians, who say that in all propositions in which yes or no is required, one of them must be true. He was afraid if this were granted in such a proposition as ‘Epicurus will be alive or dead tomorrow,’ either one or the other must necessarily be admitted. Therefore he absolutely denied the necessity of yes or no. Can anything show stupidity in a greater degree?”
Okay. So in this example, we may even have a more clear setup for where Epicurus is going and how to make sense of it. Because it’s tempting to read something like that and take a superficial view: well, this person is making a very common-sense suggestion. Either you’re going to be alive tomorrow or you’re not. Now why in the world would a common-sense philosopher like Epicurus refuse to admit that one of those things is going to be true?
And again, people accuse Epicurus of being a muddled or a superficial thinker, but I think this is a great example of the depth of his thought, because he’s pointing out to us that there are other issues involved rather than just agreeing to this proposition. And the issue that Epicurus is always wanting us to keep in our minds is what we’ve been discussing: logic is not the ultimate arbiter of reality. And those who are suggesting that you can set reality into a syllogism — and that the fact of setting something into a syllogism, like “Epicurus will be alive or dead tomorrow” or “Hermarchus will be alive or dead tomorrow” or any person — “and one of the two of them must necessarily be true” — well, it’s very tempting for us to think that that construction of words has created something that in reality must necessarily be true. But no construction of words is necessarily going to control and command reality. It’s reality that controls and commands reality.
And it is the reality that we can attempt to predict the future using words — we can do our best to describe and use our experience to predict the future. But because there is no fate and because there is no necessity, we cannot be certain that a prediction about the future is either true or false. And in adding that caveat — I believe Martin has explained to us in the past that it’s that aspect of this, the prediction of the future, that is the real issue.
Obviously we do believe that it is possible to say that certain things are true and certain things are false — and that’s the whole error with skepticism in the first place. But the attempt to predict the future is something different from making a factual statement about the present. The future has all sorts of things that are going to come into play to bring about the future. And while we can do a really good job of predicting things, the ability to predict every eventuality and to say that by necessity something is going to happen is a step too far. And Epicurus points that out to us by saying that it’s not even legitimate to ask or answer such a question.
As Cotta says: “Therefore, he absolutely denied the necessity of yes or no.” Well, that’s not to say that Epicurus doesn’t have the ability to make a pretty good prediction, just like we can. If Hermarchus is 30 years old and in peak physical condition, you can make a pretty strong prediction that he’s going to be alive tomorrow — unless he’s in the middle of a war, unless he’s taking up some dangerous occupation that would put his life in jeopardy. But it’s not the same thing to predict the future based on your rational observation of the past as it is to say that Hermarchus necessarily must be alive tomorrow. And Epicurus is always going to great lengths to point out overstatements — over-claims by logic, as if logic has the ability to compel reality. Which it does not.
Joshua: So you’re dealing with this kind of on-face value, which is taking the question to task in its own terms. DeWitt in his book Epicurus and His Philosophy puts it this way. He says: “A fourth kind of necessity was dialectical. This was simply ignored. For example, when the disjunctive proposition ‘Tomorrow Hermarchus will either be alive or dead’ was put up to Epicurus, he declined to give an answer. He was too wary a dialectician himself to swallow a dialectical bait.”
Let me give an example of maybe how this works. We have discussed a little bit the ontological argument for the existence of God from Saint Anselm. And I’m going to give you a syllogism. It’s a syllogism that even Bertrand Russell himself struggled with. There’s a famous story: he went to buy a pouch of tobacco, and while he was walking down the street he threw it up in the air and said, “The ontological argument is valid! The ontological argument is valid!” And then later on he said, “It’s easier to feel that it’s false than to demonstrate why it’s false.” And this is the problem with a priori reasoning — with reasoning without reference to facts in nature and without the ability to test the conclusions in nature.
So in the third chapter of the text called the Proslogion by Anselm, the argument is laid out in this way. Premise one: by definition, God is a being than which none greater can be imagined. Premise two: a being that necessarily exists in reality is greater than a being that does not necessarily exist. Thus, premise three: by definition, if God exists as an idea in the mind but does not necessarily exist in reality, then we can imagine something that is greater than God. Premise four: but we cannot imagine something that is greater than God. Premise five: thus, if God exists in the mind as an idea, then God necessarily exists in reality. Premise six: God exists in the mind as an idea. And then you get to seven, the conclusion: therefore, God necessarily exists in reality.
If you accept the earlier premises, you’re forced to accept the conclusion: God exists in reality.
The problem is it’s very easy to establish a syllogism using even some of his own premises and arrive at a very different conclusion. Let me see if I can do this in the moment here — it’s somewhat difficult. I will accept the first three of his premises. Let me go over them again. By definition, God is a being than which none greater can be imagined. Two: a being that necessarily exists in reality is greater than a being that does not necessarily exist. Three: thus by definition, if God exists as an idea in the mind but does not necessarily exist in reality, then we can imagine something that is greater than God.
I can take some of what Anselm is saying here and then add my own premises — which I think are true — and arrive at a different conclusion. So I could say, for example: “By definition, God is a being than which none greater can be imagined. A being that necessarily exists in reality is greater than a being that does not necessarily exist in reality. However — and I add my own premise, which I think is true — a being that has the power to choose whether or not to exist in reality in any given moment is greater than a being that only necessarily exists in reality, because a being that is not bound by necessity is greater than a being that is bound by necessity. Therefore, God can choose in any given moment whether or not to exist in reality. However, it’s not possible for humans to know in any given moment whether God has chosen to exist in reality or chosen not to exist in reality. And since we cannot know whether God has chosen to exist or chosen not to exist, it is not possible to know whether God exists in reality.”
I’m using some of Anselm’s own premises here, and the same kind of a priori logical argument that St. Anselm is using. But instead of arriving at the conclusion that God necessarily exists in reality, I’m arriving at the conclusion that it’s not possible to know whether God exists in reality. Two very contradictory conclusions arrived at by the same method of reasoning. So what do we learn from this? Do we learn that one conclusion is true and the other is not necessarily true? Or do we conclude from this that the very project of trying to prove the existence of a being in nature using an a priori logical syllogism — that that project is insufficient to demonstrate the actual existence of an actual being in nature?
And that’s the approach that I take. And that’s also the approach that David Hume takes in response. David Hume, in his book Dialogues Concerning Natural Religion, proposed that nothing can be proven to exist using only a priori reasoning. And he says this: “There is an evident absurdity in pretending to demonstrate a matter of fact or to prove it by any arguments a priori. Nothing is demonstrable unless the contrary implies a contradiction. Nothing that is distinctly conceivable implies a contradiction. Whatever we conceive as existent, we can also conceive as non-existent. There is no being therefore whose non-existence implies a contradiction. Consequently, there is no being whose existence is demonstrable.”
It’s this flaw that lies at the heart of all of these arguments that use a priori reasoning to demonstrate the existence of God. “You cannot logic a thing into existence” is the conclusion here. So when you’re dealing with a challenge like the challenge that Cotta presents here to Epicurus, sometimes the best thing to do is to say: what I’m looking for is not this approach. What I’m looking for is evidence that you can point to in nature that suggests that the conclusion you’re trying to reach using logic is true. If you can demonstrate this to be the case empirically, your conclusion will be so much stronger than any conclusion reached using only a priori logic can ever be.
And so I think there are different ways you can tackle the challenge here. But the approach — to say, “Stop. No, I’m not going to go down this path. It’s like if any one of Socrates’ interlocutors just said, ‘We’re not doing this dialectic game; just point to something in nature that we can talk about. I don’t want to get lost in the weeds of your logical miasma where nobody really seems to understand anything and we all just get confused.’” This is a bit complicated. I will link to a thread for an earlier episode where I discuss this at more length in one of my posts, and that would be a good place, I think, to examine some of the problems that are at the heart of this rigorously logical approach, which does not even attempt to test itself by reference to the effects that exist in nature.
Cassius: Joshua, I thought that was a great explanation, and your summary there at the end was very good as well. And I look forward to that link. I know that there are people out there who, as soon as they hear the words “a priori,” their eyes glaze over and their minds close shut. And through much of my life I would consider myself in that category. But as important as it is to get down in the weeds to deal with the argument, it’s also important to be able to surface above the water and be able to state this kind of problem in very clear terms that hopefully anyone can understand.
Because it’s continuously this relationship issue — between words and logic versus reality — that people need to understand. Reality and nature take priority in the end, whenever there’s a conflict between what we perceive, what nature tells us, and what our logic and our words would tell us in a different direction. You’ve got to go with nature; you’ve got to go with reality. And that’s where Epicurus is going, by talking about how even the visions of the insane and those things we see in dreams have a certain degree of truth to them, because those things that affect us are in fact real to us.
One technical point on this issue that we’ve had some debates about — exactly what it means — I’ll just go, for purposes of this discussion, with the way Bailey has translated it, and presume that Bailey has translated it correctly, because I think this sentence makes the point that you’ve just been discussing. In section 34 of Diogenes Laertius, it says that Epicurus held “of investigations, some concern actual things and others mere words.” And I would suggest that one way of getting a handle — one way of getting a grasp of this issue — is to just realize that actual things in reality are more important to us than mere words. When we’ve run into an inconsistency or a conflict or a nonsensical combination of words, we adjust our words to fit reality. We do not expect reality to adjust itself to fit our words.
Now, before we bring today’s discussion to an end, there is one more argument in this chain that Cotta brings up that we should include before we move on next week into Section 26. Because Cotta also says: “Zeno, being pressed by Arcesilaus, who pronounced all things to be false which are perceived by the senses, said that some things were false, but not all. Now Cotta is holding that up as the right position. Cotta then says: Epicurus was afraid that if any one thing seen should be false, nothing could be true — and therefore he asserted all the senses to be infallible directors of truth.” And he says, “Nothing can be more rash than this. For by endeavoring to repel a light stroke, he receives a heavy blow.”
As if Epicurus has taken an absurd position by saying that all the senses are true, because he refuses to admit that well, sometimes they’re true and sometimes they’re false. And of course that is not the right construction of Epicurus’s position, because Epicurus says that truth and falsehood reside in the mind. Truth and falsehood are matters of opinion. It is not the senses and the perceptions that are true and false. It is the construction that we give to them when we process them in our minds. Cotta is attempting to hold Epicurus up to ridicule on this point when it really is one of the strongest positions that Epicurus takes. It’s not the senses that are right and wrong — it’s our opinions about what the senses tell us that can sometimes be wrong. So Cotta is once again off on the wrong track, and Epicurus’s position is the one that makes the most sense.
Joshua: On the Wikipedia page it says: “In Athens, Arcesilaus interacted with the Pyrrhonist philosopher Timon of Phlius, whose philosophy appears to have influenced Arcesilaus to become the first Academic to adopt a position of philosophical skepticism — that is, he doubted the ability of the senses to discover truth about the world, although he may have continued to believe in the existence of truth itself. This brought in the skeptical phase of the Academy. His chief opponent was his contemporary Zeno of Citium, the founder of Stoicism, whose dogma of katalepsis — that is, that reality could be comprehended with certainty — Arcesilaus denied.”
So Cotta seems to be saying that while Arcesilaus’s position that certainty in knowledge is impossible is the best position, Cotta also thinks that Zeno’s position — which is that some things were false as perceived by the senses, but not all things as perceived by the senses are false — is a better position than Epicurus, who goes “hog wild” in saying that everything reported by the senses is true, that the senses are infallible directors of truth.
This is an issue we’ve talked about quite a lot. And one of the ways you’ve spoken about this in the past, Cassius, is that the senses report things without opinion or bias. It’s not to say that, in our minds, reasoning on what we’ve gotten through the senses, we don’t arrive at false opinions. We certainly often do arrive at false opinions about the senses. But the senses don’t lie, in the sense that they don’t add their own bias or filter to the input that’s coming in.
Speaker 3: So you’ve been presenting Epicurus’s ideas regarding how the senses are true. And at the same time, I keep flashing in my mind thinking of modern psychology and how we understand the human brain. It’s a little hard to really take that all the senses are absolutely true. So we can think that the senses are most of the time correct, and occasionally there’s some kind of error that occurs — but it’s very rare — and that makes more sense to me than saying that they’re always true. With modern psychology there’s research where they have studied what happens when people are perceiving things and when things go wrong. So from a modern understanding, we could start to see patterns, because you can’t really separate the eyes’ perception from what’s being registered. To me they’re bound together. So it’s just really hard for me to hear that the senses are always true.
Cassius: Yeah, you’re stating the same false premise that the ancients were stating, in a modern way — as if the modern world has somehow revised the way the senses operate. Epicurus’s point was hard for the ancients to understand and it’s hard for the modern ear to understand, because the word “true” has multiple meanings, has multiple senses to it.
Epicurus’s point then and his point today is the same: the eyes do not tell us anything about what they are seeing. They provide data to us about the brightness of a thing, the color of a thing — but they don’t tell us what it is they are seeing. And so it is always improper to say that the eyes are right or wrong. The eyes are never right or wrong. The eyes are relaying whatever they can. They may be astigmatic, they may be nearsighted, they may be farsighted. You may be looking through a rainstorm, you may be looking through a fog, you may be looking at night. There are innumerable ways in which what it is your mind is trying to grasp is being blocked by obstacles between you and that other thing. But when your mind is incapable of forming a true conclusion that does correspond with reality, it’s not the fault of the eyes in telling you something wrong. All the eyes can ever do is provide to you what they are wired to provide. And it is your mind that has to make the decision about what it is the eyes are presenting — and take that data that your eyes are presenting and turn it into an opinion. That is Epicurus’s point. Opinions are true or false, but the eyes, the ears, the nose — they are never false or true.
And I’m glad you said it the way you did: it’s not just modern versus ancient; it’s just these issues of the multiple definitions of words like “true.” You immediately jump to the conclusion that the word “true” means that your opinion corresponds with reality. But that’s not what the eyes are doing. It’s the same situation with gods. People are so wired to presume that gods are omnipotent and omniscient and have all these supernatural powers that they cannot separate in their minds the meaning of the word “god” from their preconceived notions. But like it or not, that’s what Epicurus is telling us: if we don’t separate these things out, we will never figure out what is really true in the world.
If we allowed preconceived definitions of words like “gods” or “true” to get in the way of us perceiving the reality of things, then we’re going to live unhappy lives. We’re never going to get nature figured out, because nature doesn’t take orders from us. Nature doesn’t let us dictate in words the way nature really is. Words are helpful, words can be important, but they can be obstacles. And if we don’t take command of the words, and look to nature for our definition of the words — if we think we’re going to define words the way we want, come hell or high water — then we are going to have hell and high water, just like the analogy to listening to your Google navigator when you’re driving off a cliff. Because the cliff is going to kill you regardless of what your Google navigator, your logical system, would lead you to believe.
That’s been the theme of what we, in attempting to defend Epicurus’s position, need to be able to unwind. There’s one more here before we close today. In the same argument, Cotta is accusing Velleius of the same thing in regard to the gods. He’s saying that on the subject of the nature of the gods, Epicurus falls into the same error: because in order to avoid the concretion of individual bodies — lest death and dissolution should be the consequence (because of course Epicurus has been holding that if a body comes together from atoms, it’s eventually going to split apart) — Cotta attacks on that point and says: “Well, Epicurus knows that death and dissolution occur if you have a body, and so therefore he denies that the gods have a body but instead says they have something like a body, and that they don’t have blood but have something like blood.”
And Cotta is saying that’s where this “quasi-” stuff is coming from — “you don’t know the right answer and you’re just submitting something that’s nonsensical.” Well, the proper response to that is what Lucretius says in Book 4, around line 500, which I’ll use to help conclude today’s episode. Because in Book 4, Lucretius says this — Bailey’s version: “If reason is unable to unravel the cause why those things which close at hand are seen square are seen round from a distance, still it is better through lack of reasoning to be at fault in accounting for the cause of either shape, rather than to let things clearly seen slip abroad from your grasp and to assail the grounds of belief and to pluck up the whole foundation on which life and existence rest. For not only would all reasoning fall away, life too itself would collapse straight away, unless you choose to trust the senses and avoid those headlong spots and all other things of this kind which must be shunned, and make for what is opposite to these. Know then that all is but an empty store of words which has been drawn up and arrayed against the senses.”
Now I’m going to maintain that the point of that is clear. For example: when you see a tower at a distance and it appears to be round, even though when you get up close to it it is square — in that situation, or in many of the situations we’re talking about today — you’re faced with an apparent contradiction. You don’t know what the real explanation is. Up close it looks square; from a distance it looks round. Are your eyes wrong when you’re a mile away and the tower looks round? You have many issues like that where your senses appear to be leading you in a direction that you think is wrong.
Well, you have to make a decision. If you don’t understand optics, if you don’t understand why things look different from a distance versus when you’re up close — what are you going to do? Are you going to say, “Well, I can’t trust my eyes; I’m just going to stop trusting my eyes. I’m going to say these things are unreliable. The eyes need to be discarded. I’m going to close them, I’m going to gouge them out”? And of course, if you do that, you’re going to die. And you deserve to die if you’re not able to figure out that what’s important to you in life is the reality that you’re dealing with, and not some logical position that “well, the eyes had always better be right all the time, or else I’m going to pluck them out.” Well, your eyes are never right or wrong. Your eyes are your eyes. And you have to understand the nature of things and how your eyes work, and be able to predict whether the distance is a problem, whether fog or other distortions are a problem — and it’s not something that you have to despair and throw away your eyes over. But you can reason through the facts and allow yourself to make accurate predictions no matter the circumstances that you’re under.
Epicurus is constantly serving the primacy of nature, the primacy of the senses. And in Book 4, Lucretius is really hammering this point home — because if you give up your confidence in your senses and your understanding of how they operate, and if you say “I’d better go looking for something else besides the senses,” that’s when you’re going to go straight headlong into Plato and his ideal forms, or Aristotle and his essences, or religion and their divine revelation. And you’re going to pick something which is really a fantasy, something made up in your mind that does not really exist, versus trusting the faculties that nature has given you to live according to nature.
So many of these questions come down to this kind of choice that has to be made. And Epicurus cannot explain to you exactly how it is that the atoms can swerve at no fixed time and no fixed place. And Epicurus cannot tell you as much as you might like to know about exactly what type of body the gods have. But he’s going to tell you that when you have reality staring itself in your face, you deal with reality. You don’t give up confidence in your senses and your natural faculties. You do the best you can and you move forward with living happily, rather than abandoning nature and guaranteeing a bad result. Let’s go ahead and bring today’s episode to a close with closing thoughts.
Joshua: Yeah, I really think that developing this distinction between this logical Platonist approach and comparing that to a more empiricist approach as we see in Epicurus really highlights one of the fault lines between these ancient thinkers. Because when Cotta says in response to Epicurus declining to take him up on dialectic — “Can anything show stupidity in a greater degree?” — well, I guess one response would be: can anything show stupidity in a greater degree, Cotta, than to assume that the conclusions of your pure logic are true even though you’ve never tested those conclusions in nature? This is the paradigm shift here between the two positions. And that conflict has not stopped — we’re still dealing with the fallout from this approach.
One last thing, Cassius. Because we’ve been talking about the atoms swerving at no particular place or time by just a small amount — there’s an article that you often cite on this question, and it bears on this discussion of truth.
Cassius: Yes, Joshua. You’re talking about David Sedley’s article on Epicurus’s refutation of determinism. And it’s very interesting how the same argument applies both to determinism and to skepticism, and that brings us back to this issue of truth. Because in that article, David Sedley is observing — in fact, he takes the position that he doesn’t think that Epicurus’s theory of the swerve was something that Epicurus came up with through physics. He thinks that yes, Epicurus adopted it and incorporated it into his physics, and made the observation that it’s impossible to be able to see that this very slight swerve does not occur — but Sedley takes the position that Epicurus really came up with the swerve as a result of what we’re talking about today: this conflict between logical necessity versus the reality of the way things really are. That’s where Epicurus made his choice to go with reality. He’s making his choice to stop his car at the edge of the cliff and not go over, no matter what the navigation says about a bridge being there. He’s going with reality always.
So it’s Epicurus’s refutation of determinism. There are two levels of truth: at the atomic level, to say that the atoms and the void exist is certainly true. But it’s also true to say that the atoms come together through the void and form bodies, and that these bodies have properties and qualities which are real and true to us. And neither perspective — neither the atomic perspective nor our perspective — has some monopoly on the truth. Both of them are true and real in their own paradigms. And just because Democritus says in the end that there’s nothing but atoms and void, that is not a reason for you to fall into despair and nihilism and think that, “Oh my gosh, I’m nothing but a bunch of dirt flying through the void, so let’s go ahead and kill ourselves because nothing really matters anyway” — like the Queen song. So again, yes, that is an excellent article. I’ll link it in the show notes today as well: “Epicurus’s Refutation of Determinism” by one of the real luminaries of Epicurean scholarship, David Sedley. Anything else, Joshua?
Joshua: I think that’s a great way to end here: by tying it back into Democritus with his claim that “of truth, we know nothing, because truth lies at the bottom of the well,” and that the only thing that really exists is the atoms and the void through which they flow — so things that seem to exist on our level of experience aren’t real or aren’t true. And that, to me, is a very corrosive approach to philosophy and to human life.
It also ties in with Einstein and his view that there are no absolute frames of reference — in other words, that something can be true from two different perspectives or two different levels of experience. I remember Richard Dawkins was trying to develop a while ago a view of what he called “middle world” — which is nature through the experience of humans and other creatures on our level of existence. For insects, forces like gravity are less important, but forces like surface tension are much more important than they are for us. You have these insects that can walk on water — well, we can’t do that because of our mass. But if you’re small enough, if you exist at that level of reality, your experience of nature is very, very different from our experience of nature. But it doesn’t mean that one of these is false and the other one is true. You have different levels at which experience can be had, and the experience is true at both levels. An interesting thing to think about, but it also applies to everything we’re talking about.
Cassius: Yeah, Joshua, you used the word “corrosive,” and that’s where we’ll close today. That’s why all of this is so fundamentally important. And people will use analogies to this — to the Pontius Pilate question in the Bible about “what is truth?” And I really think Pontius Pilate deserves a lot of credit for that question. It is the ultimate question. And it is where these people are going wrong in their analysis: by thinking that they have a monopoly on the word “truth,” and that their explanation — their word game — is what’s really true, and if you’re not consistent with their word game, then you are false and you are wrong. And that’s where Epicurus is telling us to get to the real meaning of the word “true” — to realize that it’s actual things that we’re concerned about and not simply words — and to go forward and live happily according to nature and according to the reality of nature, and not according to our imperfect methods of attempting to constrict nature into a certain set of words that conform to our opinion of the way we think things should be.
Okay, let’s close on that for today. Thanks for your time. Be sure to drop by the forum. We’ll have links to the references we’ve made today. We’ll come back next week on Section 26 of Book 1 of On the Nature of the Gods. See you then. Bye.