Canonics - The Way We Know

Key First Concepts

Key concepts include:

1. He Who Says “Nothing Can Be Known” Knows Nothing.

Knowledge is possible, and the claims of the Skeptics that nothing can be known are absurd and self-contradictory.

The second poisonous doctrine that Epicurus identified is known to us today as Radical Skepticism. Skeptics hold that nothing in life can be known with confidence. The Skeptics of Epicurus’ time argued, primarily due to their contention that the senses cannot be trusted, that we can never be certain of anything, and at most some things are “probable.” Even something as obvious as the expectation that if you jump off a canyon wall you will fall to your death is not certain to such philosophers, it is merely “probable.”

Epicurus saw that this confidence-destroying doctrine suffers much the same flaw as Determinism - it is self-contradictory nonsense. Anyone who is ridiculous and absurd enough to advocate that “nothing can be known” is taking you for a fool, because he expecting you to accept that he knows that “nothing can be known.” Epicurus held that that such arguments should not be taken seriously, any more than you should seriously accept the argument from a living person that it would be better never to have been born.

Lucretius spoke for Epicurus in writing: ” Again, if any one thinks that nothing is known, he knows not whether that can be known either, since he admits that he knows nothing. Against him then I will refrain from joining issue, who plants himself with his head in the place of his feet. And yet were I to grant that he knows this too, yet I would ask this one question; since he has never before seen any truth in things, whence does he know what is knowing, and not knowing each in turn, what thing has begotten the concept of the true and the false, what thing has proved that the doubtful differs from the certain? \[Book 4:469\]

Citations:
1. Lucretius 4:469
  1. [469] Again, if any one thinks that nothing is known, he knows not whether that can be known either, since he admits that he knows nothing. Against him then I will refrain from joining issue, who plants himself with his head in the place of his feet. And yet were I to grant that he knows this too, yet I would ask this one question; since he has never before seen any truth in things, whence does he know what is knowing, and not knowing each in turn, what thing has begotten the concept of the true and the false, what thing has proved that the doubtful differs from the certain?
2. Diogenes of Oinoanda, Fragment 5
  1. Smith: “Now Aristotle and those who hold the same Peripatetic views as Aristotle say that nothing is scientifically knowable, because things are continually in flux and, on account of the rapidity of the flux, evade our apprehension. We on the other hand acknowledge their flux, but not its being so rapid that the nature of each thing [is] at no time apprehensible by sense-perception. And indeed [in no way would the upholders of] the view under discussion have been able to say (and this is just what they do [maintain] that [at one time] this is [white] and this black, while [at another time] neither this is [white nor] that black, [if] they had not had [previous] knowledge of the nature of both white and black.”
Notes:

2. All Sensations Are True.

The senses report what they observe truthfully and without opinion of their own. Error is in what the mind does with the senses, not in the senses themselves.

If Skepticism and Determinism are false, what did Epicurus advocate instead? Epicurus saw that much of the error of conventional thinkers arises from their contention that the faculties given us by nature are incapable of ascertaining truth, and that we have no need of divine revelation or abstract syllogistic logic to determine what is really true. Epicurus vigorously rejected these assertions, and held that the faculties given to us by nature - the five senses, the feelings of pleasure and pain, and the mental anticipatory faculty of prolepsis - are fully sufficient for living in accord with nature.

Epicurus identified that the perceptions of our natural faculties are not at all the same thing as the opinions which we form after processing those perceptions in our minds. Our natural faculties report their perceptions to the mind “truly,” in the sense of “honestly,” without adding any overlay of opinion of their own. Neither the eyes nor the ears nor any other faculty have any memory, and they simply relay to the mind what they perceive at any moment. It is the mind which turns perceptions into opinions. The eyes do not tell our minds what they see and the ears do not tell our minds what they hear, and so on. Truth and error is in the mind’s formation of opinion, not in the faculties given by nature.

The task of determining truth is that of the mind, which requires that we understand both nature and how our faculties process the perceptions provided to us by nature. Our faculties are our only direct contacts with outside reality. As Lucretius wrote as to our “feelings” in general: ” For that body exists is declared by the feeling which all share alike; and unless faith in this feeling be firmly grounded at once and prevail, there will be naught to which we can make appeal about things hidden, so as to prove aught by the reasoning of the mind.” (Book 1:418)

Epicurus held that the Natural Faculties are (1) The Anticipations Or “Prolepsis”, (2) The Five Senses, and (3) The Faculty Of Pleasure And Pain. Epicurus held that Illusions Do Not Invalidate The Senses, and that we must consider not only what the eyes, ears, nose, tongue, and sense of touch tell us, but also what our minds receive directly in the form of Images from the outside world.

Epicurus taught that we should defer to the Priority Of Nature Over “Logic,” and that we should reject “Dialectic” as a source of knowledge. He taught the importance of Practical Deductive Reasoning, of Clarity, and of “Waiting” before making a decision where multiple possibilities that are consistent with observation support different conclusions. Epicurus held that in some cases we cannot obtain certainty and the elmination of all but one possibilities, so we must at times allow that Multiple Possibilities may be true. The selection of one possibility among many, when many are equally supported by the evidence, is therefore seen as arbitrary and capricious.

Major Implications: Error does not occur in the senses, but in the mind in forming opinions about what the sensations are reporting.
Citations:
1. Epicurus to Herodotus 38 - [We] must keep all our investigations in accord with our sensations, and in particular with the immediate apprehensions whether of the mind or of any one of the instruments of judgment, and likewise in accord with the feelings existing in us, in order that we may have indications whereby we may judge both the problem of sense perception and the unseen. … Moreover, the universe is bodies and space: for that bodies exist, sense itself witnesses in the experience of all men, and in accordance with the evidence of sense we must of necessity judge of the imperceptible by reasoning, as I have already said.
2. Lucretius 1:418 - For that body exists is declared by the feeling which all share alike; and unless faith in this feeling be firmly grounded at once and prevail, there will be naught to which we can make appeal about things hidden, so as to prove aught by the reasoning of the mind.
3. Lucretius 4:478 - You will find that the concept of the true is begotten first from the senses, and that the senses cannot be gainsaid. For something must be found with a greater surety, which can of its own authority refute the false by the true. Next then, what must be held to be of greater surety than sense? Will reason, sprung from false sensation, avail to speak against the senses, when it is wholly sprung from the senses? For unless they are true, all reason too becomes false.
4. Torquatus speaking for Epicurus in On Ends 1:64 - Moreover, unless the constitution of the world is thoroughly understood, we shall by no means be able to justify the verdicts of our senses. Further, our mental perceptions all arise from our sensations; and if these are all to be true, as the system of Epicurus proves to us, then only will cognition and perception become possible. Now those who invalidate sensations and say that perception is altogether impossible, cannot even clear the way for this very argument of theirs when they have thrust the senses aside. Moreover, when cognition and knowledge have been invalidated, every principle concerning the conduct of life and the performance of its business becomes invalidated.
  Epicurus to Herodotus 51 - (Yonge) “And, on the other side, error could not be possible, if we did not receive some other motion also, a sort of initiative of intelligence connected, it is true, with direct representation, but going beyond that representative. These conceptions being connected with direct perception which produces the representation, but going beyond it.”
5. Epicurus On Nature Book 28, Sedley trans, fr. 13, col. 6 inf. - “I also frequently reflected that if, when I raised difficulties which someone might have turned against us, he should claim that what used to be assimilated from ordinary language was the same as used to be practiced in the written work, many might well conclude that in those days false opinion was represented in that language, whether through an empirical process, an image-based process, or a theoretical process, or through a non-empirical process, not following one of our current divisions, but simply arising from an internal movement; but that now, because the means of expression is adapted to additional ends, discrimination provides a lead towards the truth. However, let no one ever try to get even with you by linking with you any trace of this suspicion; but [turn] to the entire faculty of empirical reasoning…
6. (Aetius 4.8.10) “Leucippus, Democritus, and Epicurus say that sensation and thought arise in the soul from images that approach from outside, for neither of these can occur to anyone without the image falling upon him.”
7. (Aetius 4.9.5 - 6) “Epicurus says that every sensation and every impression is true, but of the opinions some are true and some false; and sensation gives us a false picture in one respect only, namely with regard to objects of thought; but the impression does so in two respects, for there is impression of both sense objects and objects of thought. Parmenides, Empedocles, Anaxagoras, Democritus, Epicurus, and Heraclides say that the particular sensations of their own object occur in accordance with the matching sized of the pores, each of the sense objects corresponding to each sense.”
8. Notes:
9. Discussion Forum

3. Change Is Constant, But Not So Fast That Knowledge Is Impossible.

Those who say that the existence of change means that nothing is knowable are speaking absurdly and falsely. The universe does constantly change, but not at so fast a rate that we are not able to grasp that which is real to us.

4. The Tests Of Truth Are The Five Senses, The Prolepses (Anticipations), And The Feelings Of Pleasure And Pain.

That which is true to us is determined through the proper use of the five senses, the mind’s ability to recognize patterns, and the feelings of pleasure and pain, not through dialectical logic or divine revelation.

5. Those Things At The Perceptible Level Which We Establish Through Our Senses, Prolepses, And Feelings Are No Less Real Than Those Things At The Imperceptible Level Which We Establish Through Deduction.

The qualities and properties of the things that the senses reveal to us are no less true, and no less real, than the conclusions of logic about the atoms and void from which the things around us are made.

Key Takeaways

About many important things knowledge is possible. It is absurd for radical skeptics to argue that nothing at all can be known, because he who argues that nothing can be known is making an argument that is self-contradictory.
The conclusions about which we are confident are those which are validated by evidence obtained through the primary faculties given us by Nature, which are (1) the five senses, (2) the feelings of pleasure and pain, and (3) the pattern-recognizing faculty called “anticipations” (from the Latin) or “prolepsis” (from the Greek).
These natural faculties are reliable sources of knowledge because they report to us honestly without adding any opinions of their own.
The phrase “All sensations are true” is correct from the perspective that the senses report “truly,” in the sense of “honestly” without bias or prejudice.
If we lose the courage to trust our senses as the basis of our knowledge, we lose our grasp not only on proper reasoning, but also our grasp on life itself.
Where the evidence provided by the senses, feelings, and anticipations is conflicting or insufficient to arrive at a single conclusion, it is appropriate to “wait” before accepting any conclusion as true, and where multiple conclusions are consistent with the evidence, it is appropriate to hold all of them as possibly true until evidence becomes available by which only one can be selected as true.

II. Canonics - Knowledge Is Possible And Essential To Happiness*

And he taught us that unless, at the very first, we have confidence in our senses as to those things which are clear and apparent to us, there will be nothing to which we can appeal when we seek to prove, by reasoning of the mind, anything about those things which are hidden. (Lucretius Book 1, line 420) -[^5]
Thus the wise man will hold firmly to that which is true, and he will not be a mere skeptic. [(Diogenes Laertius, Book X)]
Yet there are some men who will claim that nothing at all can be known. As for these, they know not whether even their own claim can be known, since they admit that they know nothing. [(Lucretius Book 4)]
We therefore decline to argue with men who place their head where their feet should be. And yet, even if we granted their claim that they know nothing, we would still ask these questions: [(Lucretius Book 4)]
Since they have never yet seen any truth in any thing, how do they know what “knowing” and “not knowing” are? What is it that has produced in them this knowledge of the true and the false? What is it that has proved to them the difference between the doubtful and the certain? [(Lucretius Book 4)]
That which is able to refute the false must by nature be provable with a higher certainty to be true. And what can fairly be accounted of higher certainty than sensation? [(Lucretius Book 4)]
Can reasoning alone contradict the senses, when reasoning itself is wholly founded on the senses? If the senses are not true, all reasoning is rendered false as well. [(Lucretius Book 4)]
So if by reasoning you are unable to explain why a thing close at hand appears square, but at a distance appears round, it is far better for you to state that you do not know the reason, rather than to let slip from your grasp your confidence in sensing those things that are clear. [(Lucretius Book 4)]
For if you lose your confidence in your senses, you will ruin the groundwork and foundation on which all of your life and existence rest. [(Lucretius Book 4)]
Not only would reason collapse, but life itself would fall to the ground, were you to lose confidence in your senses and fail to use them to shun those pitfalls in life which must be avoided. [(Lucretius Book 4)]
Just as when you erect a building, if your ruler is crooked, your square is untrue, and your level is sloped, then your construction will be faulty, without symmetry, and leaning, with its parts disposed to fall - all ruined by the first erroneous measurements. [(Lucretius Book 4)]
So too will all your efforts at reasoning about things be distorted and false if the sensations on which your reasoning is based are unreliable. [(Lucretius Book 4)]
Therefore, as we reason, we must grasp firmly the ideas which we attach to words, so that we may thereafter be able to refer to those words with confidence, and not leave everything uncertain, or go on explaining to infinity with words devoid of meaning. [(Epicurus, Letter to Herodotus)]
Thus while we direct our greatest and highest interests by reason throughout our whole life, we do not rely either on dialectical reason or logic as our ultimate Canon of Truth. [(Epicurus Doctrine 16, Epicurus’ Letter to Herodotus, Diogenes Laertius Book 10)]
Instead, the faculties which constitute our Canon of Truth are our senses, our preconceptions, and our feelings of pleasure and pain, for it is by means of these that we test those things which are true, and we determine which are obscure and need confirmation. [(Epicurus’ Letter to Herodotus)]
For only when those things which are clear to us are understood is it time to consider those things which are obscure. [(Epicurus’ Letter to Herodotus)]
Now, apply your mind, for a new question struggles earnestly to gain your ears, a new aspect of things is about to display itself. [(Lucretius Book 2)]
Do not be dismayed by the novelty of my words: weigh these matters with keen judgment, and if they seem to you to be true, embrace them, or if they be false, gird yourself to battle them. [(Lucretius Book 2)]
Just as dogs discover by smell the lair of a wild beast that is covered over with leaves, you, by yourself alone, must learn to see one thing after another, and find your way into dark corners to draw forth the truth. [(Lucretius Book 1)]
Think carefully on these things, and then, one step after another, the true path will grow clear. Not even the darkest night will rob you of the road, for each step will light the torch for the next. [(Lucretius Book 1)]

General Significance of the Canon

Diogenes Laertius, Lives of Philosophers, X.31: In The Canon Epicurus states that the sensations, the prolepses, and the passions are the criteria of truth.
Cicero, On End-Goals, Good and Bad, I.19.63 (Torquatus to Cicero): Besides, it is only by firmly grasping a well-established scientific system, observing the standard or Canon that has fallen as it were from heaven, so that all men may know it – only by making that Canon the test of all our judgments, that we can hope always to stand fast in our belief, unshaken by the eloquence of any man.
Cicero, On Ends, Book 1. [63] It was indeed excellently said by Epicurus that fortune only in a small degree crosses the wise man’s path, and that his greatest and most important undertakings are executed in accordance with his own design and his own principles, and that no greater pleasure can be reaped from a life which is without end in time, than is reaped from this which we know to have its allotted end. He judged that the logic of your school possesses no efficacy either for the amelioration of life or for the facilitation of debate. He laid the greatest stress on natural science. That branch of knowledge enables us to realize clearly the force of words and the natural conditions of speech and the theory of consistent and contradictory expressions; and when we have learned the constitution of the universe we are relieved of superstition, are emancipated from the dread of death, are not agitated through ignorance of phenomena, from which ignorance, more than any thing else, terrible panics often arise; finally, our characters will also be improved when we have learned what it is that nature craves. Then again if we grasp a firm knowledge of phenomena, and uphold that canon, which almost fell from heaven into human ken, that test to which we are to bring all our judgments concerning things, we shall never succumb to any man’s eloquence and abandon our opinions.
[64] Moreover, unless the constitution of the world is thoroughly understood, we shall by no means be able to justify the verdicts of our senses. Further, our mental perceptions all arise from our sensations; and if these are all to be true, as the system of Epicurus proves to us, then only will cognition and perception become possible. Now those who invalidate sensations and say that perception is altogether impossible, cannot even clear the way for this very argument of theirs when they have thrust the senses aside. Moreover, when cognition and knowledge have been invalidated, every principle concerning the conduct of life and the performance of its business becomes invalidated. So from natural science we borrow courage to withstand the fear of death, and firmness to face superstitious dread, and tranquility of mind, through the removal of ignorance concerning the mysteries of the world, and self-control, arising from the elucidation of the nature of the passions and their different classes, and as I shewed just now, our leader again has established the canon and criterion of knowledge and thus has imparted to us a method for marking off falsehood from truth.

The Importance of Clarity

Link to Letter to Herodotus

[37] Wherefore since the method I have described is valuable to all those who are accustomed to the investigation of nature, I who urge upon others the constant occupation in the investigation of nature, and find my own peace chiefly in a life so occupied, have composed for you another epitome on these lines, summing up the first principles of the whole doctrine. First of all, Herodotus, we must grasp the ideas attached to words, in order that we may be able to refer to them and so to judge the inferences of opinion or problems of investigation or reflection, so that we may not either leave everything uncertain and go on explaining to infinity or use words devoid of meaning.
[38] For this purpose it is essential that the first mental image associated with each word should be regarded, and that there should be no need of explanation, if we are really to have a standard to which to refer a problem of investigation or reflection or a mental inference. And besides we must keep all our investigations in accord with our sensations, and in particular with the immediate apprehensions whether of the mind or of any one of the instruments of judgment, and likewise in accord with the feelings existing in us, in order that we may have indications whereby we may judge both the problem of sense perception and the unseen.

The Use of Outlines

Link to Letter to Herodotus

For those who are unable, Herodotus, to work in detail through all that I have written about nature, or to peruse the larger books which I have composed, I have already prepared at sufficient length an epitome of the whole system, that they may keep adequately in mind at least the most general principles in each department, in order that as occasion arises they may be able to assist themselves on the most important points, in so far as they undertake the study of nature. But those also who have made considerable progress in the survey of the main principles ought to bear in mind the scheme of the whole system set forth in its essentials.
For we have frequent need of the general view, but not so often of the detailed exposition. Indeed it is necessary to go back on the main principles, and constantly to fix in one’s memory enough to give one the most essential comprehension of the truth. And in fact the accurate knowledge of details will be fully discovered, if the general principles in the various departments are thoroughly grasped and borne in mind; for even in the case of one fully initiated the most essential feature in all accurate knowledge is the capacity to make a rapid use of observation and mental apprehension, and this can be done if everything is summed up in elementary principles and formulae. For it is not possible for anyone to abbreviate the complete course through the whole system, if he cannot embrace in his own mind by means of short formulae all that might be set out with accuracy in detail.

We Must First Have Confidence In Our Ability to Judge That Which is Right In Front of Us Before We Can Speculate About Things That Are More Remote

Letter to Herodotus

[38] For this purpose it is essential that the first mental image associated with each word should be regarded, and that there should be no need of explanation, if we are really to have a standard to which to refer a problem of investigation or reflection or a mental inference. And besides we must keep all our investigations in accord with our sensations, and in particular with the immediate apprehensions whether of the mind or of any one of the instruments of judgment, and likewise in accord with the feelings existing in us, in order that we may have indications whereby we may judge both the problem of sense perception and the unseen. … Moreover, the universe is bodies and space: for that bodies exist, sense itself witnesses in the experience of all men, and in accordance with the evidence of sense we must of necessity judge of the imperceptible by reasoning, as I have already said.

Lucretius Book One

[418] For that body exists is declared by the feeling which all share alike; and unless faith in this feeling be firmly grounded at once and prevail, there will be naught to which we can make appeal about things hidden, so as to prove aught by the reasoning of the mind.

The Flux And Our Ability To Comprehend It

Diogenes of Oinoanda On The Flux

Link to Text

Fr. 5: [Others do not] explicitly [stigmatise] natural science as unnecessary, being ahamed to acknowledge [this], but use another means of discarding it. For, when they assert that things are inapprehensible, what else are they saying than that there is no need for us to pursue natural science? After all, who will choose to seek what he can never find?
Now Aristotle and those who hold the same Peripatetic views as Aristotle say that nothing is scientifically knowable, because things are continually in flux and, on account of the rapidity of the flux, evade our apprehension. We on the other hand acknowledge their flux, but not its being so rapid that the nature of each thing [is] at no time apprehensible by sense-perception. And indeed [in no way would the upholders of] the view under discussion have been able to say (and this is just what they do [maintain] that [at one time] this is [white] and this black, while [at another time] neither this is [white nor] that black, [if] they had not had [previous] knowledge of the nature of both white and black.

The Nature of Images

Letter to Herotodus

[46] Moreover, there are images like in shape to the solid bodies, far surpassing perceptible things in their subtlety of texture. For it is not impossible that such emanations should be formed in that which surrounds the objects, nor that there should be opportunities for the formation of such hollow and thin frames, nor that there should be effluences which preserve the respective position and order which they had before in the solid bodies: these images we call idols.
[47] Next, nothing among perceptible things contradicts the belief that the images have unsurpassable fineness of texture. And for this reason they have also unsurpassable speed of motion, since the movement of all their atoms is uniform, and besides nothing or very few things hinder their emission by collisions, whereas a body composed of many or infinite atoms is at once hindered by collisions. [48] Besides this, nothing contradicts the belief that the creation of the idols takes place as quick as thought. For the flow of atoms from the surface of bodies is continuous, yet it cannot be detected by any lessening in the size of the object because of the constant filling up of what is lost. The flow of images preserves for a long time the position and order of the atoms in the solid body, though it is occasionally confused. Moreover, compound idols are quickly formed in the air around, because it is not necessary for their substance to be filled in deep inside: and besides there are certain other methods in which existences of this sort are produced. For not one of these beliefs is contradicted by our sensations, if one looks to see in what way sensation will bring us the clear visions from external objects, and in what way again the corresponding sequences of qualities and movements.
[49] Now we must suppose too that it is when something enters us from external objects that we not only see but think of their shapes. For external objects could not make on us an impression of the nature of their own colour and shape by means of the air which lies between us and them, nor again by means of the rays or effluences of any sort which pass from us to them — nearly so well as if models, similar in color and shape, leave the objects and enter according to their respective size either into our sight or into our mind; moving along swiftly, and so by this means reproducing the image of a single continuous thing and preserving the corresponding sequence of qualities and movements from the original object as the result of their uniform contact with us, kept up by the vibration of the atoms deep in the interior of the concrete body.
[50] And every image which we obtain by an act of apprehension on the part of the mind or of the sense-organs, whether of shape or of properties, this image is the shape or the properties of the concrete object, and is produced by the constant repetition of the image or the impression it has left. Now falsehood and error always lie in the addition of opinion with regard to what is waiting to be confirmed or not contradicted, and then is not confirmed or is contradicted.
[51] For the similarity between the things which exist, which we call real and the images received as a likeness of things and produced either in sleep or through some other acts of apprehension on the part of the mind or the other instruments of judgment, could never be, unless there were some effluences of this nature actually brought into contact with our senses. And error would not exist unless another kind of movement too were produced inside ourselves, closely linked to the apprehension of images, but differing from it; and it is owing to this, supposing it is not confirmed, or is contradicted, that falsehood arises; but if it is confirmed or not contradicted, it is true.
[52] Therefore we must do our best to keep this doctrine in mind, in order that on the one hand the standards of judgment dependent on the clear visions may not be undermined, and on the other error may not be as firmly established as truth and so throw all into confusion. Moreover, hearing, too, results when a current is carried off from the object speaking or sounding or making a noise, or causing in any other way a sensation of hearing. Now this current is split up into particles, each like the whole, which at the same time preserve a correspondence of qualities with one another and a unity of character which stretches right back to the object which emitted the sound: this unity it is which in most cases produces comprehension in the recipient, or, if not, merely makes manifest the presence of the external object.
[53] For without the transference from the object of some correspondence of qualities, comprehension of this nature could not result. We must not then suppose that the actual air is molded into shape by the voice which is emitted or by other similar sounds — for it will be very far from being so acted upon by it — but that the blow which takes place inside us, when we emit our voice, causes at once a squeezing out of certain particles, which produce a stream of breath, of such a character as to afford us the sensation of hearing. Furthermore, we must suppose that smell too, just like hearing, could never bring about any sensation, unless there were certain particles carried off from the object of suitable size to stir this sense-organ, some of them in a manner disorderly and alien to it, others in a regular manner and akin in nature.
[54] Moreover, we must suppose that the atoms do not possess any of the qualities belonging to perceptible things, except shape, weight, and size, and all that necessarily goes with shape. For every quality changes; but the atoms do not change at all, since there must needs be something which remains solid and indissoluble at the dissolution of compounds, which can cause changes; not changes into the nonexistent or from the non-existent, but changes effected by the shifting of position of some particles, and by the addition or departure of others. For this reason it is essential that the bodies which shift their position should be imperishable and should not possess the nature of what changes, but parts and configuration of their own. For thus much must needs remain constant.
[55] For even in things perceptible to us which change their shape by the withdrawal of matter it is seen that shape remains to them, whereas the qualities do not remain in the changing object, in the way in which shape is left behind, but are lost from the entire body. Now these particles which are left behind are sufficient to cause the differences in compound bodies, since it is essential that some things should be left behind and not be destroyed into the non-existent. Moreover, we must not either suppose that every size exists among the atoms, in order that the evidence of phenomena may not contradict us, but we must suppose that there are some variations of size. For if this be the case, we can give a better account of what occurs in our feelings and sensations.
[56] But the existence of atoms of every size is not required to explain the differences of qualities in things, and at the same time some atoms would be bound to come within our ken and be visible; but this is never seen to be the case, nor is it possible to imagine how an atom could become visible.

Discussion Of Images In Lucretius

Qualities (Events or Accidents) and Properties

The Nature of Properties (Attributes Which Have An Eternal Existence And Do Not Change Over Time)

Lucretius Book 1 - [449] For all things that have a name, you will find either properties linked to these two things or you will see them to be their accidents. That is a property which in no case can be sundered or separated without the fatal disunion of the thing, as is weight to rocks, heat to fire, moisture to water, touch to all bodies, intangibility to the void.

Letter to Herodotus - [54] Moreover, we must suppose that the atoms do not possess any of the qualities belonging to perceptible things, except shape, weight, and size, and all that necessarily goes with shape. For every quality changes; but the atoms do not change at all, since there must needs be something which remains solid and indissoluble at the dissolution of compounds, which can cause changes; not changes into the nonexistent or from the non-existent, but changes effected by the shifting of position of some particles, and by the addition or departure of others. For this reason it is essential that the bodies which shift their position should be imperishable and should not possess the nature of what changes, but parts and configuration of their own. For thus much must needs remain constant.

Letter to Herodotus - [55] For even in things perceptible to us which change their shape by the withdrawal of matter it is seen that shape remains to them, whereas the qualities do not remain in the changing object, in the way in which shape is left behind, but are lost from the entire body. Now these particles which are left behind are sufficient to cause the differences in compound bodies, since it is essential that some things should be left behind and not be destroyed into the non-existent.

Letter to Herodotus - [69] Moreover, as regards shape and colour and size and weight and all other things that are predicated of body, as though they were concomitant properties either of all things or of things visible or recognizable through the sensation of these qualities, we must not suppose that they are either independent existences (for it is impossible to imagine that), nor that they absolutely do not exist, nor that they are some other kind of incorporeal existence accompanying body, nor that they are material parts of body: rather we should suppose that the whole body in its totality owes its own permanent existence to all these, yet not in the sense that it is composed of properties brought together to form it (as when, for instance, a larger structure is put together out of the parts which compose it, whether the first units of size or other parts smaller than itself, whatever it is), but only, as I say, that it owes its own permanent existence to all of them. All these properties have their own peculiar means of being perceived and distinguished, provided always that the aggregate body goes along with them and is never wrested from them, but in virtue of its comprehension as an aggregate of qualities acquires the predicate of body.

Letter to Herodotus - [70] Furthermore, there often happen to bodies and yet do not permanently accompany them accidents, of which we must suppose neither that they do not exist at all nor that they have the nature of a whole body, nor that they can be classed among unseen things nor as incorporeal. So that when according to the most general usage we employ this name, we make it clear that accidents have neither the nature of the whole, which we comprehend in its aggregate and call body, nor that of the qualities which permanently accompany it, without which a given body cannot be conceived.

Letter to Herodotus - [71] But as the result of certain acts of apprehension, provided the aggregate body goes along with them, they might each be given this name, but only on occasions when each one of them is seen to occur, since accidents are not permanent accompaniments. And we must not banish this clear vision from the realm of existence, because it does not possess the nature of the whole to which it is joined nor that of the permanent accompaniments, nor must we suppose that such contingencies exist independently (for this is inconceivable both with regard to them and to the permanent properties), but, just as it appears in sensation, we must think of them all as accidents occurring to bodies, and that not as permanent accompaniments, or again as having in themselves a place in the ranks of material existence; rather they are seen to be just what our actual sensation shows their proper character to be.

The Nature of Qualities, Such As The The Trojan War, Which Do Not Have Eternal Existence And Do Change Over Time (Also Referred To As Events or Accidents)

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[449] For all things that have a name, you will find either properties linked to these two things or you will see them to be their accidents. That is a property which in no case can be sundered or separated without the fatal disunion of the thing, as is weight to rocks, heat to fire, moisture to water, touch to all bodies, intangibility to the void. On the other hand, slavery, poverty, riches, liberty, war, concord, and other things by whose coming and going the nature of things abides untouched, these we are used, as is natural, to call accidents. Even so time exists not by itself, but from actual things comes a feeling, what was brought to a close in time past, then what is present now, and further what is going to be hereafter. And it must be avowed that no man feels time by itself apart from the motion or quiet rest of things. [464] Then again, when men say that ‘the rape of Tyndarus’s daughter’, or ‘the vanquishing of the Trojan tribes in war’ are things, beware that they do not perchance constrain us to avow that these things exist in themselves, just because the past ages have carried off beyond recall those races of men, of whom, in truth, these were the accidents. For firstly, we might well say that whatsoever has happened is an accident in one case of the countries, in another even of the regions of space. Or again, if there had been no substance of things nor place and space, in which all things are carried on, never would the flame of love have been fired by the beauty of Tyndaris, nor swelling deep in the Phrygian heart of Alexander have kindled the burning battles of savage war, nor unknown of the Trojans would the timber horse have set Pergama aflame at dead of night, when the sons of the Greeks issued from its womb. So that you may see clearly that all events from first to last do not exist, and are not by themselves like body, nor can they be spoken of in the same way as the being of the void, but rather so that you might justly call them the accidents of body and place, in which they are carried on, one and all.

Color As An Example of An Event / Accident / Quality

Letter to Herodotus - [49] Now we must suppose too that it is when something enters us from external objects that we not only see but think of their shapes. For external objects could not make on us an impression of the nature of their own colour and shape by means of the air which lies between us and them, nor again by means of the rays or effluences of any sort which pass from us to them — nearly so well as if models, similar in color and shape, leave the objects and enter according to their respective size either into our sight or into our mind; moving along swiftly, and so by this means reproducing the image of a single continuous thing and preserving the corresponding sequence of qualities and movements from the original object as the result of their uniform contact with us, kept up by the vibration of the atoms deep in the interior of the concrete body.

U30 Plutarch, Against Colotes, 7, p. 1110C: It is not hard to see that this reasoning may be applied to every object called or commonly held to be biter, sweet, cathartic, soporific, or luminous: that none has a self-contained quality or potency or is more active than passive on entering the body, but acquires different properties as it blends with different bodies. Accordingly, Epicurus himself in the second book Against Theophrastus, when he says that colors are not intrinsic to bodies but a result of certain arrangements and positions relative to the eye, is asserting by this reasoning that body is no more colorless than colored. Earlier in the word, he writes word for word as follows: “{= U29}, True, it often happens that when objects are enveloped in air of the same degree of darkness, some people perceive a distinction of color while others whose eyesight is weak do not; again, on first entering a dark room we see no color, but do after waiting a short time.” Therefore no body will any more be said to have color than not. If color is relative, white and blue will be relative; and if these, then also sweet and bitter, so that of every quality we can truly say, “It is no more this than it is not this;” for to those affected in a certain way the thing will be this, but not to these not so affected.

Reason Is Dependent On The Senses

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Error Is Added By The Mind, Not By The Senses

Lucretius Book 4 - [462] Wondrously many other things of this sort we see, all of which would fain spoil our trust in the senses; all in vain, since the greatest part of these things deceives us on account of the opinions of the mind, which we add ourselves, so that things not seen by the senses are counted as seen. For nothing is harder than to distinguish things manifest from things uncertain, which the mind straightway adds of itself.

Anyone Who Argues Nothing Can Be Known Admits That He Knows Nothing

Lucretius Book 4 - [469] Again, if any one thinks that nothing is known, he knows not whether that can be known either, since he admits that he knows nothing. Against him then I will refrain from joining issue, who plants himself with his head in the place of his feet. And yet were I to grant that he knows this too, yet I would ask this one question; since he has never before seen any truth in things, whence does he know what is knowing, and not knowing each in turn, what thing has begotten the concept of the true and the false, what thing has proved that the doubtful differs from the certain?

Reason Derives Its Authority From The Senses

Lucretius Book 4 - [478] You will find that the concept of the true is begotten first from the senses, and that the senses cannot be gainsaid. For something must be found with a greater surety, which can of its own authority refute the false by the true. Next then, what must be held to be of greater surety than sense? Will reason, sprung from false sensation, avail to speak against the senses, when it is wholly sprung from the senses? For unless they are true, all reason too becomes false. Or will the ears be able to pass judgement on the eyes, or touch on the ears? or again will the taste in the mouth refute this touch; will the nostrils disprove it, or the eyes show it false? It is not so, I trow. For each sense has its faculty set apart, each its own power, and so it must needs be that we perceive in one way what is soft or cold or hot, and in another the diverse colours of things, and see all that goes along with colour. Likewise, the taste of the mouth has its power apart; in one way smells arise, in another sounds. And so it must needs be that one sense cannot prove another false. Nor again will they be able to pass judgement on themselves, since equal trust must at all times be placed in them. Therefore, whatever they have perceived on each occasion, is true.

Life Itself Depends On Trusting The Senses

Lucretius Book 4 - [500] And if reason is unable to unravel the cause, why those things which close at hand were square, are seen round from a distance, still it is better through lack of reasoning to be at fault in accounting for the causes of either shape, rather than to let things clear seen slip abroad from your grasp, and to assail the grounds of belief, and to pluck up the whole foundations on which life and existence rest. For not only would all reasoning fall away; life itself too would collapse straightway, unless you chose to trust the senses, and avoid headlong spots and all other things of this kind which must be shunned, and to make for what is opposite to these. Know, then, that all this is but an empty store of words, which has been drawn up and arrayed against the senses.

If The Senses Are False Then All Reasoning Sprung From Them Is False

Lucretius Book 1 - [418] But now, to weave again at the web, which is the task of my discourse, all nature then, as it is of itself, is built of these two things: for there are bodies and the void, in which they are placed and where they move hither and thither. For that body exists is declared by the feeling which all share alike; and unless faith in this feeling be firmly grounded at once and prevail, there will be naught to which we can make appeal about things hidden, so as to prove aught by the reasoning of the mind. And next, were there not room and empty space, which we call void, nowhere could bodies be placed, nor could they wander at all hither and thither in any direction; and this I have above shown to you but a little while before.
Lucretius Book 4 - [513] Again, just as in a building, if the first ruler is awry, and if the square is wrong and out of the straight lines, if the level sags a whit in any place, it must needs be that the whole structure will be made faulty and crooked, all awry, bulging, leaning forwards or backwards, and out of harmony, so that some parts seem already to long to fall, or do fall, all betrayed by the first wrong measurements; even so then your reasoning of things must be awry and false, which all springs from false senses.

Reasoning By Analogy To The Familiar

Epicurus’ Letter to Pythocles The wanings of the moon and its subsequent waxings … may be explained in all the ways in which phenomena on earth invite us to such explanations of these phases, if only one does not fall in love with the method of a single explanation (μοναχῇ τρόπος ) and groundlessly disapproves of others, without having considered what it is possible for a human being to observe and what it is not and, for this reason, desirous of observing things that cannot be observed’.
Epicurus’ On Nature XI

[Line Ia11-19; Sedley] The sun, if we walk towards the place from which it appeared to us] to rise, directing ourselves up into the mainland zone, appears to us to set where we previously passed by, sometimes even when we have moved in all only a short distance. And this time we cannot blame it on the latitudinal movements. Why after all should you declare the measurement from here, or the one from here, or the one from here, or this one a more reliable guide of the risings and settings (of the sun)?

Epicurus’ On Nature XI

[Line IIa1 - 21; Sedley] They cannot hope] to form a [mental] model ([ὁ]μοίωμα) and to reason out (συλλογίζεσθαι) anything about these matters. For it seems to me that when they spend their time contriving some of them (I means their [ὄρ]γανα, instruments) and fooling around with others, it is no wonder, in view not only of the enslavements brought upon them by their doctrines but also (as far as concerns the appearances of the sun) of the indeterminacies (ἀοριστείας) of risings and settings, that they cannot form an adequate mental model by means of their instruments which produce no regularity. But their instruments are …

Principal Doctrines Relevant to Canonics

PD22. We must consider both the real purpose, and all the evidence of direct perception, to which we always refer the conclusions of opinion; otherwise, all will be full of doubt and confusion.

PD23. If you fight against all sensations, you will have no standard by which to judge even those of them which you say are false.

PD24. If you reject any single sensation, and fail to distinguish between the conclusion of opinion, as to the appearance awaiting confirmation, and that which is actually given by the sensation or feeling, or each intuitive apprehension of the mind, you will confound all other sensations, as well, with the same groundless opinion, so that you will reject every standard of judgment. And if among the mental images created by your opinion you affirm both that which awaits confirmation, and that which does not, you will not escape error, since you will have preserved the whole cause of doubt in every judgment between what is right and what is wrong.

PD25. If on each occasion, instead of referring your actions to the end of nature, you turn to some other, nearer, standard, when you are making a choice or an avoidance, your actions will not be consistent with your principles.

Vatican Sayings Relevant to Canonics

VS24. Dreams have no divine character nor any prophetic force, but they originate from the influx of images.

Diogenes Laertius Section on Canonics

Link to Text (Bailey - Warning - Note that he uses ‘concept’ instead of ‘preconception’)

[29] I will also give you the Principal Doctrines, and a selection from his sayings which seem most worthy of mention. You will thus be able to understand Epicurus from every point of view and could form a judgment on him. The first letter he writes to Herodotus (and it deals with Physics; the second is to Pythocles), and it deals with Celestial Phenomena; the third is to Menoeceus, and contains the moral teaching. We must begin with the first letter, but I will first speak briefly about the divisions of his philosophy.
[30] It is divided into three parts, the Canonicon (or Procedure), the Physics and the Ethics. The Canonicon gives the method of approach to the system, and is contained in the work called The Canon. The Physics contains all the investigation into nature, and is contained in the thirty-seven books On Nature and in an abridged form in the letters. The Ethics deals with choice and avoidance, and is contained in the books On Lives and the letters and the book on The End. The Epicureans usually group the Canonicon with the Physics and state that it deals with the criterion of truth and the fundamental principles and contains the elements of the system. The Physics deals with creation and dissolution and with nature; the Ethics with things to be chosen or avoided, with the conduct of life and its purpose.
[31] Logic they reject as misleading. For they say it is sufficient for physicists to be guided by what things say of themselves. Thus in The Canon Epicurus says that the tests of truth are the sensations and concepts and the feelings; the Epicureans add to these the intuitive apprehensions of the mind. And this he says himself too in the summary addressed to Herodotus and in the Principal Doctrines. For, he says, all sensation is irrational 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. [32] Nor is there anything which can refute the sensations. For a similar sensation cannot refute a similar because it is equivalent in validity, nor a dissimilar a dissimilar, for the objects of which they are the criteria are not the same; nor again can reason, for all reason is dependent upon sensations; nor can one sensation refute another, for we attend to them all alike. Again, the fact of apperception confirms the truth of the sensations. 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. For all thoughts have their origin in sensations by means of coincidence and analogy and similarity and combination, reasoning 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.
[33] The concept [preconception] they speak of as an apprehension or right opinion or thought or general idea stored within the mind, that is to say a recollection of what has often been presented from without, as for instance ‘Such and such a thing is a man,’ for the moment the word ‘man’ is spoken, immediately by means of the concept his form too is thought of, as the senses give us the information. Therefore the first signification of every name is immediate and clear evidence. And we could not look for the object of our search, unless we have first known it. For instance, we ask, ‘Is that standing yonder a horse or a cow?’ To do this we must know by means of a concept the shape of horse and of cow. Otherwise we could not have named them, unless we previously knew their appearance by means of a concept. So the concepts are clear and immediate evidence. Further, the decision of opinion depends on some previous clear and immediate evidence, to which we refer when we express it: for instance, ‘How do we know whether this is a man?’
[34] 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 was 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. The internal sensations they say are two, pleasure and pain, which occur to every living creature, and the one is akin to nature and the other alien: by means of these two choice and avoidance are determined. Of investigations some concern actual things, others mere words. This is a brief summary of the division of their philosophy and their views on the criterion of truth.

The Map Is Not The Territory

A recurring issue involves keeping a clear focus on the distinction between abstractions and feelings, such as the different uses of the word “happiness” (“I feel happy” vs “To me happiness means XXXX.” ) References relevant to this issue include:

Torquatus:

Hence Epicurus refuses to admit any necessity for argument or discussion to prove that pleasure is desirable and pain to be avoided. These facts, be thinks, are perceived by the senses, as that fire is hot, snow white, honey sweet, none of which things need be proved by elaborate argument: it is enough merely to draw attention to them. (For there is a difference, he holds, between formal syllogistic proof of a thing and a mere notice or reminder: the former is the method for discovering abstruse and recondite truths, the latter for indicating facts that are obvious and evident.)ap

Letter to Herodotus:

First of all, Herodotus, we must grasp the ideas attached to words, in order that we may be able to refer to them and so to judge the inferences of opinion or problems of investigation or reflection, so that we may not either leave everything uncertain and go on explaining to infinity or use words devoid of meaning. [38] For this purpose it is essential that the first mental image associated with each word should be regarded, and that there should be no need of explanation, if we are really to have a standard to which to refer a problem of investigation or reflection or a mental inference. And besides we must keep all our investigations in accord with our sensations, and in particular with the immediate apprehensions whether of the mind or of any one of the instruments of judgment, and likewise in accord with the feelings existing in us, in order that we may have indications whereby we may judge both the problem of sense perception and the unseen.

Diogenes Laertius:

The internal sensations they say are two, pleasure and pain, which occur to every living creature, and the one is akin to nature and the other alien: by means of these two choice and avoidance are determined. Of investigations some concern actual things, others mere words. This is a brief summary of the division of their philosophy and their views on the criterion of truth.