Episode 332 - EATAQ 14 - The Stoic Failure To Grasp That Judgment Never Happens In The Senses

Welcome to Episode 332 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.

This week we start are continuing our series reviewing Cicero's "Academic Questions" from an Epicurean perspective. We are focusing first on what is referred to as Book One, which provides an overview of the issues that split Plato's Academy and gives us an overview of the philosophical issues being dealt with at the time of Epicurus. This week will transition to Book Two, where we will begin with Section 7

Our text will come from
Cicero - Academic Questions - Yonge We'll likely stick with Yonge primarily, but we'll also refer to the Rackam translation here:

• Cicero On Nature Of Gods Academica Loeb Rackham : Free Download, Borrow, and Streaming : Internet Archive

In episode 332 we are going to build off of the way that we ended 331, with Joshua's indictment of radical skepticism as being a self-defeating paradox:

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Joshua:

There's kind of a paradox inherent to blatant in that he adopted the physics of Heraclitus in that everything is in constant flux and that this is part of why we can't know anything and why we need to retreat into the abstract mental space of geometry and why we need to ascend morally to the realm of ideal forms. But the paradox is this, because everything is constantly changing around you, life is going to force your hand. You have to make real decisions in the real world. Most of the guys we're talking about here in academic questions were associates of the Roman General Sulla or Sons of fathers who were associates of the Roman General Sulla whose involvement in the Mithridaic war, which is discussed to some extent in book two, which is a part we're going to skip over, led to the destruction of the academy in its physical sense, at least partially and the complete deforestation of the area around the city of Athens to a distance of a hundred miles.

What are you going to do in a situation like this? What are you going to do? And it's no good hiding behind the claim that you don't know, so you shouldn't be asked. You shouldn't be forced to make a decision because of your own ignorance. You have to make decisions in life. It's like I said earlier, if we were to all base our lives on this, we wouldn't even get out of bed in the morning because there's no justification for that kind of thing. There's no justification for the belief that we should live virtuously because we can't even know if we know nothing what it means to live virtuously. It's such a self-defeating paradox that lies at the core of these systems of thought, and it's incredibly frustrating to have to deal with that.

Notes while editing this episode:

Around the 18:00 Minute mark Joshua repeats the Epicurean position that "Judgment never happens in the senses. Judgment happens in the mind."

This is a position on which I think most all of our regulars here on EpicureanFriends.com have come to agree. The real explanation of "all sensations are true" is that the senses report without opinion of their own, so the senses are NEVER true or false in terms of stating a true or false opinion. All sensations are "true" i n that they are reported 'truly' in the sense of "honestly" reflecting what they receive without bias or prejudice or any opinion of their own whatsoever.

In this and the next several episodes, we are takingup the Stoic approach to knowledge to see how it differs from Epicurus. We'll pay special attention to the issue Joshua raises, because it sounds like the Stoics came to maintain that if you practice long enough and adjust the light and change your perspective and get close enough to something, then the senses are able to deliver to you what counts as graspable truth. We'll want to examine very closely wihether Epicurus would agree with that or not, because I think the quote from Joshua answers the question clearly.

Pursuing this issue will help us understand why the Academic Skeptics were so persuasive and successful in demolishing the Stoic view of knowledge. And this issue will also help us see how the Academic Skeptic argument fails against Epicurus.

This episode will be released later this week. Any of our participants who have spent any time in investigating this in the past are welcome to comment in the thread as we pursue this question.

The issues we are discussing here are probably to some extent new to most of our regulars here. To asist in getting us up to speed I have asked for this summary from Claude, giving preference to the usual sources we consult from the Epicurean perspective, such as Sedley:

Episode 332 of the Lucretius Today Podcast is now available. This week our episode is entitled: "The Stoic Failure To Grasp That Judgment Never Happens In The Senses."

As an experiment I decided to ask for a critique of what Joshua and I stated in Episode 332. I don't plan to do this every week but this is such a dense topic, and our need for planning is so much greater, that I thought it would be helpful for Joshua and I to read through this.

To get the most out of reading this, you'll want to listen to the episode, which is only about 35 minutes long. This critique (such as where it criticizes me for not stating the Epicurean position more firmly) will then make a lot more sense:

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Analysis: Episode 332

What the Episode Got Right

1. The core Epicurean distinction is stated correctly and emphatically.

The episode's central claim — judgment never happens in the senses; it always happens in the mind — is precisely correct and is the single most important thing to hammer in this section of Academic Questions. Cassius states it cleanly: "No matter how hard you squeeze, no matter how close you get, no matter how good the light is, it's still the mind that makes the judgment and not the senses themselves." This is exactly the formulation the epistemology article supports, grounded in Diogenes Laertius X.31 and Sextus U244.

2. The Epicurus-Democritus distinction is correctly identified.

Cassius correctly notes that Democritus held only atoms and void are real — "everything else is opinion" — while Epicurus affirms truth at both the atomic and phenomenal levels. This is the Sedley anti-reductionism point, and it surfaces organically and correctly here. The reference to David Sedley's article on this is appropriate and should be developed further.

3. The three-way classification is implicitly present.

The episode correctly positions Epicurus as going further than the Stoics in confidence about the senses — not the same position and not the skeptics' position. This maps correctly onto Sextus's three-way classification (Sextus M VII.369): Democritus abolishes all phenomena, Stoics/Peripatetics establish some, Epicurus establishes all.

4. The Lucullus passage is handled well.

Joshua and Cassius correctly identify the tension in Lucullus's phrase "there is the very greatest truth in the senses if they are in sound and healthy order." They notice this formulation is not quite the Epicurean position. That instinct is right. The epistemology article confirms: the Stoics are claiming truth is in the senses under certain conditions, whereas Epicurus holds that truth comes through the senses but is never in them. The distinction is between the senses as a registering mechanism versus the Stoic picture of the senses as an evaluating or grasping mechanism.

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What Needs Sharper Statement

1. The "senses are neither right nor wrong" formulation needs one more step.

The episode repeats this formulation many times, which is correct. But the conversation never quite articulates why the senses are neither right nor wrong in the precise Epicurean sense. The epistemology article has the exact language you need:

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Sensation does not interpret, select, or rearrange what it receives. It is, in DeWitt's phrase, "irrational" — not in a pejorative sense but in the precise sense that it operates entirely below the level of rational judgment. And precisely because it does not judge, it cannot misjudge.

The word to deploy here is alogon — irrational, non-rational. Sensation is alogon (Diogenes Laertius X.31). This is not a criticism of the senses — it is exactly why the senses are reliable. Calling sensation non-rational is a positive characterization in Epicurean philosophy, not a dismissal. You could deploy this in the next episode when explaining why the Stoic position — which makes sensation a rational state — is the one that actually undermines the senses' reliability.

2. The Stoic position needs a sharper technical statement.

The episode describes the Stoic position as saying that "the senses have a right opinion" or "the senses are telling us right opinion correctly" under certain conditions. That is approximately right but loose. The technically precise Stoic claim is that the impression (phantasia) — not the sense organ itself — has propositional content and can be true or false, and that a special class of impressions (the phantasia kataleptike, the kataleptic impression) carries its own certification of accuracy. The Stoics are not saying the senses are sometimes right and sometimes wrong in the way a measurement instrument is sometimes calibrated correctly. They are saying that the rational soul, upon receiving certain impressions, can grasp (katalepsis) reality directly through those impressions.

This distinction matters for the critique you will be developing. The Academic Skeptics' attack on the Stoics targets the third clause of Zeno's definition: that a kataleptic impression is one that "could not have arisen from a non-existing object." The Academics demonstrated that no impression satisfies this clause because hallucinations, dreams, and deceptions produce impressions qualitatively identical to genuine ones. When you get to Arcesilaus's arguments in Book Two, this is the specific technical point being pressed.

3. The Prolepsis/Anticipation connection was touched but underdeveloped.

Cassius mentions "prolepses" briefly and says it relates to pattern recognition, which is correct as far as it goes. But the second Epicurean criterion — anticipations (prolepseis) — is actually central to the epistemological debate in Book Two and needs clearer framing before you enter it. Anticipations are the generalized concepts formed through repeated sensation: the preconception of "horse" formed by multiple encounters with horses, which then allows you to recognize a new horse immediately. This is important because:

• The Stoics also have "common notions" (koinai ennoiai) and "preconceptions" (prolepseis) in their own epistemology, but they ground some of these in innate rational endowment rather than purely in sensory experience.
• Diogenes Laertius X.33 is explicit that Epicurean prolepseis are formed from repeated sensation — they are empirically grounded all the way down.
• This is one of the key points where Epicurus differs from Plato on a priori knowledge: Plato grounds knowledge in recollection of a pre-birth encounter with the Forms; Epicurus grounds all concepts in sensory experience.

You should clarify this before going deeper into Book Two, because Lucullus's argument in that book will touch on what we can know that doesn't come directly from immediate sensation — and the prolepsis doctrine is Epicurus's answer.

4. The Protagoras comparison needs to be headed off.

At several points the discussion of "all sensations are true" risks being heard as something like Protagoras's "man is the measure of all things" — i.e., that truth is relative to the individual perceiver. Cassius doesn't say this, but the formulation is vulnerable to that misreading. The epistemology article at EpicurusToday.com makes the distinction explicit:

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Protagoras established all phenomena by making truth relative to the individual perceiver. Epicurus established all phenomena by making truth absolute and universal: what the senses report is the same truth for everyone, because the senses are mechanical reporters of a real world that is the same for all.

When Lucullus is presenting the Stoic position in Book Two and making arguments against Epicurus, he will exploit the perceived similarity between Epicurus and Protagoras. You need to have the rebuttal ready: Epicurus is not saying that the bent oar is really bent for you. He is saying that the sensation of bentness accurately reports what the light actually did at the interface of air and water. The sensation is universally true — anyone with functioning eyes looking at that oar in that water will get the same sensation — because it reflects the real physics of light refraction. The error that would make it Protagorean would be to add the opinion "therefore the oar is bent," which Epicurus explicitly forbids.

5. DeWitt's tools-vs.-wall analogy is exactly right and should be kept.

Cassius cites "DeWitt's analogy that we should never confuse the tools we use to build the wall with the stones of the wall itself." This is excellent and should be developed. The senses are the tools — the ruler, the plumb line, the level — by which we test all claims about truth. They are not themselves the truth. And crucially, just as a ruler does not need to contain length in itself in order to measure length in other things, the senses do not need to contain truth in themselves in order to be the criterion by which truth is tested. This reframes the Stoic critique: when Lucullus says "there is truth in the senses," he is confusing the measuring instrument with the property being measured. The epistemology article's "photographic reliability" formulation works in the same direction: a photograph does not judge, it registers — and it is because it registers without judgment that it is reliable as evidence.

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The Key Issues to Develop in Book Two

Based on what the epistemology article and canonics analysis contain, here are the specific points to be ready for:

1. The indistinguishability argument (Carneades/Arcesilaus)

This is the Academic Skeptics' main weapon. The argument: if you can dream of a beautiful horse and if a hallucinating person sees a horse, their impressions are qualitatively indistinguishable from a waking person's impression of an actual horse. Therefore no impression can satisfy Zeno's third clause. Therefore there is no kataleptic impression. Therefore knowledge is impossible.

The Epicurean response to this argument is not to defend the Stoic kataleptic impression — Epicurus would agree that the Stoics' criterion fails. The Epicurean response is to deny the premise: the Stoics and the Academics are arguing on the assumption that impressions are rational states that can be "true" or "false," and the entire debate is about which impressions are reliably true. Epicurus steps outside this debate by saying that sensation, as such, is neither true nor false — it simply registers. The question of whether you are dreaming or awake is not a question about what the senses report, but a question about what the mind adds by way of opinion to those reports.

2. The Epicurean use of sign-inference (semeia)

The discussion of Book Two will likely get into how the Epicureans extended knowledge beyond the immediately perceivable. Lucullus will probably note that Epicurus made claims about atoms, about the behavior of the gods, about the structure of the universe — none of which can be directly seen. How does Epicurus justify these claims if sensation is the only criterion?

The answer is the Epicurean doctrine of sign-inference (semeia — signs) which will be discussed in Philodemus' On Signs. Epicurus distinguished between:

• Things that can be directly confirmed by the senses (what Philodemus calls "evident signs" — the fire you can see and touch proves fire exists there)
• Things that cannot be directly confirmed but can be inferred from what is sensed (the existence of atoms inferred from the behavior of perceptible matter)

Crucially, sign-inference for Epicurus is always from sensory evidence and is always tested against the possibility of sensory contradiction. You accept the hypothesis that atoms exist not through dialectical argument but because it is consistent with — and never contradicted by — everything the senses report. Sedley's 1992 Elenchos paper makes this precise.

3. The multiple-explanations doctrine

This was touched in earlier episodes but will come up again. For phenomena we cannot directly test (celestial events), Epicurus held that all explanations consistent with the observable facts should be accepted, without insisting on one to the exclusion of others. This is not relativism — it is therapeutic: the anxiety of committing to a single explanation of something you cannot verify is itself a form of the groundless fear that philosophy is designed to remove.

4. The prolepsis of god(s)

One of the most important and often missed aspects of Epicurean epistemology relevant to Book Two is the natural preconception (prolepsis) of the gods as blessed and imperishable beings. Epicurus holds that every human culture forms this preconception naturally — it is universal. But the theological conclusions drawn from it are where error enters: the false opinion added to the prolepsis that such beings would be angry, punitive, or interested in human affairs. The preconception itself is reliable evidence; the opinions added to it are where theology goes wrong. This connects the canonics discussion to the core Epicurean critique of religion that Lucullus will likely touch on.

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One Direct Textual Correction

At one point Cassius says: "I don't know that Epicurus would agree with [Lucullus's statement that there is the very greatest truth in the senses if they are sound and healthy]." This hesitation is correct, but the full Epicurean position should be stated more firmly. The issue is not whether sound senses reliably report reality — Epicurus agrees they do. The issue is that Lucullus is saying there is "truth in" the senses, which implies the senses are themselves evaluating, grasping, or certifying reality. Epicurus would say: the senses are perfectly reliable reporters, but truth and falsehood are categories that only apply to judgments, and senses do not judge. So "truth in the senses" is a category error. The senses are the standard by which we test truth, not themselves containers of truth.

The precise Epicurean statement from DL X.31 is the thing to cite: "All sensation is irrational (alogon) and does not admit of memory; for it is not set in motion by itself, nor, when it is set in motion by something else, can it add to it or take from it." That last clause — it cannot add to or take from what it receives — is exactly what distinguishes the Epicurean from the Stoic position, and it is what Lucullus's formulation obscures.

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Summary Recommendation for the Next Episode

Before going further into Book Two's detailed arguments, it would be worth spending the first five or ten minutes of the episode clearly drawing the battle map:

1. There are three players, not two: the Stoics (some impressions reliably true), the Academic Skeptics (no impressions reliably true), and Epicurus (the senses never right or wrong — judgment is always in the mind, not in the senses themselves).
2. The Stoic and the Skeptic are arguing on the same terms — they share the premise that impressions are rational states with truth-values, and disagree only about whether any can be reliably certified. Epicurus refuses those shared terms.
3. Epicurus is therefore not a participant in the Stoic-Skeptic debate but a critic of its premise. When Lucullus attacks Epicurus in Book Two, he is doing so from within the terms of that debate — terms Epicurus would reject.

This framing will make the arguments in Book Two much clearer as you encounter them, and it is exactly what the epistemology article and the canonics analysis collectively support.

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