Welcome to Episode 335 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, which gives us an overview of the issues that split Plato's Academy and helps us understand Epicurus' position on the same issues. This week will continue in Book Two, where we will finish up Section 7 and take up Section 8
Our text will come from
Cicero - Academic Questions - Yonge We'll likely stick with Yonge primarily, but we'll also refer to the Rackham translation here:
Last week we incorporated material from Wikipedia and Diogenes Laertius on the Stoics.
This week we will likely jump off from this short section of the Internet Encyclopedia of Philosophy on "Ancient Greek Skepticism", as this is largely what we are about to hear from Cicero when Lucullus finishes speaking:
ii. Attack on the Stoics
In general, the Stoics were the ideal target for the skeptics; for, their confidence in the areas of metaphysics, ethics and epistemology was supported by an elaborate and sophisticated set of arguments. And, the stronger the justification of some theory, the more impressive is its skeptical refutation. They were also an attractive target due to their prominence in the Hellenistic world. Arcesilaus especially targeted the founder of Stoicism, Zeno, for refutation. Zeno confidently claimed not only that knowledge is possible but that he had a correct account of what knowledge is, and he was willing to teach this to others. The foundation of this account is the notion of katalêpsis: a mental grasping of a sense impression that guarantees the truth of what is grasped. If one assents to the proposition associated with a kataleptic impression, i.e. if one experiences katalepsis, then the associated proposition cannot fail to be true. The Stoic sage, as the perfection and fulfillment of human nature, is the one who assents only to kataleptic impressions and thus is infallible.
Arcesilaus argued against the possibility of there being any sense-impressions which we could not be mistaken about. In doing so, he paved the way for future Academic attacks on Stoicism. To summarize the attack: for any sense-impression S, received by some observer A, of some existing object O, and which is a precise representation of O, we can imagine circumstances in which there is another sense-impression S’, which comes either (i) from something other than O, or (ii) from something non-existent, and which is such that S’ is indistinguishable from S to A. The first possibility (i) is illustrated by cases of indistinguishable twins, eggs, statues or imprints in wax made by the same ring (Lucullus 84-87). The second possibility (ii) is illustrated by the illusions of dreams and madness (Lucullus 88-91). On the strength of these examples, Arcesilaus apparently concluded that we may, in principle, be deceived about any sense-impression, and consequently that the Stoic account of empirical knowledge fails. For the Stoics were thorough-going empiricists and believed that sense-impressions lie at the foundation of all of our knowledge. So if we could not be certain of ever having grasped any sense-impression, then we cannot be certain of any of the more complex impressions of the world, including what strikes us as valuable. Thus, along with the failure to establish the possibility of katalepsis goes the failure to establish the possibility of Stoic wisdom (see Hankinson [1995], Annas [1990] and Frede [1983/1987] for detailed discussions of this epistemological debate).
just a brief comment on where we are going on the podcast at the moment:
1 - We're going through Academic Questions to help us get a general grounding on the issues of knowledge and skepticism as they were understood at the time that Epicurean philosophy was flourishing in the ancient world.
2 - When we finish what we decide to do with Academic Questions (we don't have the time to go through every word of it), we are going to be in a position to tackle - and we will tackle - what's left of Philodemus' "On Signs" / "On Methods of Inference"
3 - And in case it's not clear where all this leads:
As best I can tell, those who claim to be modern Stoics have pretty much abandoned any interest in the true Stoic theory of knowledge. I am sure that there are many reasons for that, but I strongly suspect that one of the primary reasons is that modern Stoics in general run from the truth that Stoicism is essentially a theistic philosophy that makes no sense outside a supernatural-based intelligent design view of the universe.
We - at least the EpicureanFriends forum in general - are not going to take that position of neglect and supression in regard to Epicurus. The main hurdle we have is not that Epicureanism starts with a false view of the universe, or that we suspect the truth of the radical skepticism that overtook the Academics and other ancient philosophers. Our hurdle today is that for generations everyone has chosen to focus exclusively on tranquility and other issues which can be reconciled with the dominant Judeo-Christianity and Humanist mix that passes for moral consensus. As a result, most of us have very little understanding of the fundamentals what Epicurus was actually teaching - even in ethics. In canonics, most of us have only a tenuous idea - at best - of what the "prolepsis" discussion is all about.
By the time we finish with "On Signs" we should have a very clear understanding of the general direction of the Epicurean theory of knowledge. At that point I expect that most of us will then be in a position to confidently assert the Epicurean view of knowledge as one of the foundational aspects of Epicurean philosophy that it certainly is. And the rest won't have any reason for confusion about what it is they are actually rejecting.
To close with a good word for those who are "actual" Stoics - even today -- At least they aren't radical Skeptics! ![]()
In today's Sunday zoom we spent virtually the entire session addressing the question of how to separate sensations from prolepsis from concepts. I am posting this in the podcast thread because it relates directly to what we are currently discussing in Cicero's "Academic Questions." I am taggin the main participants in today's zoom: Martin, Raphael Raul Patrikios Bryan . Of course anyone else is welcome to respond too.
In this podcast episode Joshua and I struggled with this following paragraph (among others). It is critical to understand that this is Lucullus speaking from a Stoic perspective, so the following is not the Epicurean view, but similar issues are being addressed so we need to compare the terminology especially where underlined:
QuoteBut such as those things are which we say are perceived by the senses, such also are those things which are said to be perceived, not by the senses themselves, but by the senses after a fashion; as these things — that is white, this is sweet, that is tuneful, this is fragrant, that is rough. We have these ideas already comprehended by the mind, not by the senses. Again, this is a house, that is a dog. Then the rest of the series follows, connecting the more important links; such as these, which embrace, as it were, the full comprehension of things; — If he is a man, he is a mortal animal partaking of reason: — from which class of arguments the notions of things are impressed upon us, without which nothing can be understood, nor inquired into, nor discussed. But if those notions were false, (for you seemed to me to translate ἔννοιαι notions,) if, I say, they were false, or impressed, or perceptions of such a kind as not to be able to be distinguished from false ones; then I should like to know how we were to use them? and how we were to see what was consistent with each thing and what was inconsistent with it?
It can become very difficult to speak precisely about these things, but here in this paragraph we seem to have (if Yonge translates correctly) every one of these underlined references being referred to as, or close to, "notions."
We need to be clear from an Epicurean perspective the extent to which Epicurus would agree or disagree with this paragraph.
To make the distinction sharper, we can ask the question: Of the underlined illustrations, which if any, are in Epicurean terms:
1) sensations
2) prolepsis / anticipations / preconcepts
3) "notions"
4) concepts
Which of the underlined illustrations fit in one or some or all of these categatories?
Cicero's On Ends does not contain nearly as much information about the Stoic view of Kataleptic impressions (that we can use to compare against Epicurus' views) as does his "Academic Questions," but it does contain this:
5 He began: "It is the view of those whose system I adopt, that immediately upon birth (for that is the proper point to start from) a living creature feels an attachment for itself, and an impulse to preserve itself and to feel affection for its own constitution and for those things which tend to preserve that constitution; while on the other hand it conceives an antipathy to destruction and to those things which appear to threaten destruction. In proof of this opinion they urge that infants desire things conducive to their health and reject things that are the opposite before they have ever felt pleasure or pain; this would not be the case, unless they felt an affection for their own constitution and were afraid of destruction. But it would be impossible that they should feel desire at all unless they possessed self-consciousness, and consequently felt affection for themselves. This leads to the conclusion that it is love of self which supplies the primary p235 impulse to action. 17 Pleasure on the contrary, according to most Stoics, is not to be reckoned among the primary objects of natural impulse; and I very strongly agree with them, for fear lest many immoral consequences would follow if we held that nature has placed pleasure among the earliest objects of desire. But the fact of our affection for the objects first adopted at nature's prompting seems to require no further proof than this, that there is no one who, given the choice, would not prefer to have all the parts of his body sound and whole, rather than maimed or distorted although equally serviceable.
"Again, acts of cognition (which we may term comprehensions or perceptions, or, if these words are distasteful or obscure, katalēpseis), — these we consider meet to be adopted for their own sake, because they possess an element that so to speak embraces and contains the truth. This can be seen in the case of children, whom we may observe to take pleasure in finding something out for themselves by the use of reason, even though they gain nothing by it. 18 The sciences also, we consider, are things to be chosen for their own sake, partly because there is in them something worthy of choice, partly because they consist of acts of cognition and contain an element of fact established by methodical reasoning. The mental assent to what is false, as the Stoics believe, is more repugnant to us than all the other things that are contrary to nature.
"(Again,5 of the members or parts of the body, some appear to have been bestowed on us by nature for the sake of their use, for example the hands, legs, feet, and internal organs, as to the degree of whose utility even physicians are not agreed; p237 while others serve no useful purpose, but appear to be intended for ornament: for instance the peacock's tail, the plumage of the dove with its shifting colours, and the breasts and beard of the male human being.) 19 All this is perhaps somewhat baldly expressed; for it deals with what may be called the primary elements of nature, to which any embellishment of style can scarcely be applied, nor am I for my part concerned to attempt it. On the other hand, when one is treating of more majestic topics the style instinctively rises with the subject, and the brilliance of the language increases with the dignity of the theme." "True," I rejoined; "but to my mind, any clear statement of an important topic possesses excellence of style. It would be childish to desire an ornate style in subjects of the kind with which you are dealing. A man of sense and education will be content to be able to express his meaning plainly and clearly."
Cassius May 29, 2026 at 11:34 AM
Episode 335 of the Lucretius Today Podcast is now available. This week our episode is entitled: "Epicurean Analysis Of Stoic Claims About Notions And Memory"
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