On Nature

Reading 4

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The source for the following text is

Book 10 of Diogenes Laertius’ Lives and Opinions of Eminent Philosophers.

All section numbers are part of Book 10. For example, section 35, or [35], is 10.35.

__________

EPICURUS to Herodotus, greeting. [35]

I have already prepared an epitome of my whole system, Herodotus, for those who are unable to study carefully all my writings about nature or to investigate the longer treatises I have composed on the subject. I have done this so they may keep in mind the principal teachings. In this way, whenever the occasion arises, they may be able to aid themselves on the most important points—at least as far as they have taken up the study of nature.

As for those who have made some advance in the survey of the whole system, they should fix in mind an elementary outline of the whole treatment of the subject. After all, in comparison with a comprehensive view of things, the details are rarely necessary.

[36] We must continually return to and memorize this elementary outline for a few reasons. One, doing so will help us to obtain a valid understanding of the facts. Two, once we have rightly understood and mastered the outline, we will have the means by which we may discover all the other details. It is the privilege of the mature student to make a ready use of his apprehensions or perceptions by referring every one of them to elementary facts and simple terms. It is impossible, after all, to gather up the results of an ongoing, diligent study of the entirety of things, unless we can summarize in short formulas and hold in mind all that may be accurately expressed down to the smallest detail.

[37] Therefore, since such a course is of service to all who take up natural science, I, who devote my continuous energy to the subject and reap the calm enjoyment of a life like this, have prepared for you such an epitome and manual of the doctrines as a whole.

General Method—Terms and Criteria

In the first place, Herodotus, we must understand what each word means. This way we will be in the position to test opinions, inquiries, or problems by utilizing the meaning of each word. Accordingly, our proofs will not run on untested endlessly, nor will the terms we use be empty of meaning. [38] The primary sense of every term employed must be clearly understood. It should require no demonstration. That way we will have a foundation or reference point for the issue, problem, or opinion before us.

Next, we must by all means stick to our sensations, that is, simply to the present impressions—whether of the mind or of any criterion whatsoever—and similarly to our actual feelings. This way we may have the means of determining that which needs confirmation and that which is obscure.

The Everlasting and Unlimited Nature of the

Cosmos and Its Constituent Parts

Now that we have clearly understood these things, it is time to consider some general points that are obscure.

To begin with, nothing comes into being out of what is non-existent. Otherwise, everything could come into being from everything, and there would be no need for any seeds.

[39] Next, if that which disappears is so absolutely destroyed so that it ceases to exist, then everything would soon perish since the disappearing things would be dissolved into that which is non-existent.

Furthermore, the sum total of things—which is to say, everything—was always the same as it is now, and such it will always remain. The reason for this is that there is nothing else into which it can change. For there is nothing beyond the sum total of things that can enter it in order to produce the change.

Moving on, the sum total of things consists of bodies and void.[i]The existence of bodies is everywhere attested by sensation itself. And recall, reason must rely on sensation when it attempts to infer the unknown from the known. [40] And if there were not the void—that which we also call “place” and “intangible nature”—bodies would have nothing in which to be and through which to move, as they are plainly seen to move. Beyond bodies and the void, there is nothing that we can conceive to exist, whether by mental apprehension or by means of analogy.

When we speak of bodies and the void, both are regarded as wholes or separate things, not as the properties or accidents of wholes or separate things. Regarding bodies, some are composite, and others are the elements out of which these composite bodies are made.[ii] [41] These elements are indivisible and unchangeable. Otherwise, everything would eventually be destroyed and pass into non-existence. As it is, however, everything is strong enough to endure when the composite bodies are broken up because the elements possess a solid nature and are incapable of being anywhere or in any way dissolved. It follows, therefore, that the first things must be indivisible, corporeal entities.

To make another point, the sum of things is infinite. For that which is finite has an extremity, and the extremity of anything is discernable only in comparison with something else. Since the sum of things has no discernable extremity, it has no limit. And since it has no limit, it must be unlimited or infinite.

Moreover, the sum of things is unlimited both in terms of the multitude of bodies and the magnitude of the void. [42] For if the void were infinite and bodies finite, then the bodies would not have remained in position anywhere. Rather, they would have been scattered in their flight through the infinite void, not having any supports or counterchecks to stabilize them after ricocheting off other bodies. On the other hand, if the void were finite, then the infinite number of bodies would not have anywhere to be.

Furthermore, the indivisible bodies, full as they are since they have no emptiness in them—the atoms out of which composite bodies arise and into which they are dissolved—vary indefinitely in their shapes. For the great variety of things we see could never have come into being out of a recurrence of a definite number of the same shapes. Atoms of each shape, those that are like one another in shape, are absolutely infinite in number. On the other hand, the variety of shapes, though indefinitely large, is not absolutely infinite.[iii]

[43] Atoms are in continual motion through the ages.[iv]Some of them rebound to a considerable distance from other atoms, while others merely oscillate in one place when they happen to get entangled with or are enclosed by a mass of other atoms shaped for entangling. [44] This oscillation occurs because each atom is separated from the rest by the void, which is incapable of offering any resistance to the rebound. By contrast, it is the solidity of the atom that makes it rebound after a collision, however short the distance to which it rebounds when it finds itself imprisoned in a mass of entangling atoms. There is no beginning of this since both the atoms and the void are forever existent.[v]

[45] The rehearsal at such length of all that we are now recalling to mind furnishes an adequate outline for our conception of the nature of existing things.

But one last related point. There is an infinite number of worlds, some like this world and others unlike it. This is so because the atoms, being infinite in number as has just been demonstrated, are transported ever further in their course. For the atoms out of which a world might arise, or by which a world might be formed, have not all been expended on one world or a finite number of worlds, whether like or unlike this one. So then, there is nothing that prevents an infinity of worlds.

Sense Perception—Seeing, Hearing, and Smelling

Seeing [46] Moving on, there are impressions—outlines or films of things—that have the same shape as solid bodies, even though they differ from them in their thinness in a way that far exceeds the thinness of any other object we see. For it is not impossible that there should be found in the surrounding air combinations of this kind—materials adapted for expressing the hollowness and thinness of surfaces, and effluxes preserving the same relative position and motion that they had in the solid objects from which they come. We give the name “images” to these outlines or films.

Furthermore, so long as nothing comes in the way to offer resistance, motion through the void accomplishes any imaginable distance in an inconceivably short period of time. This is so because resistance encountered is the same as slowness, whereas the absence of resistance is the same as speed.

[47] By the way, if we consider the minute times perceptible by reason alone, the moving body itself simultaneously arrives at more than one place. But this is impossible. That said, it does arrive simultaneously in time perceptible by sensation, however different the point of departure is from that conceived by us. For if it changed its direction, that would be equivalent to its meeting with resistance, even if up to that point we allow nothing to impede the rate of its flight. This is an elementary fact that, in itself, is well worth keeping in mind.

In the next place, the exceeding thinness of the images is contradicted by none of the facts that we may observe. Consequently, their velocities are also enormous since they find an easy passage everywhere. Moreover, their endless emanation encounters no resistance, or very little—even though many atoms, not to say an unlimited number, do at once encounter resistance.

[48] One should also keep in mind that the production of the images is as quick as thought. For particles are continually flowing from the surface of bodies, even though no reduction of the bodies is observed because other particles take their place. And those given off preserve for a long time the position and arrangement that their atoms had when they formed part of the solid bodies—although occasionally they are thrown into confusion. Sometimes such images are formed very rapidly in the air, as they do not require any solid content. And there are other modes in which they may be formed. Regardless, there is nothing in all this that is contradicted by sensation—if we look at the clear evidence of sensation, to which we should also refer the continuity of particles in the objects that are external to us.

[49] We must also consider that it is by the entrance of something coming from external objects that we see their shapes and think of them. For external objects would not stamp on us their own nature of color and shape—whether through the air, which is between the external things and us, or by means of rays of light, or by currents of any sort going from us to the externals—if certain films or images coming from the things themselves, and thus having the same color and shape as the external things themselves, did not enter into our eyes or minds, into whichever one their size is suitable.

[50] These images move with rapid motion. This explains why they present the appearance of a single continuous object when they strike our senses, and why they retain the original relationship they had with the object. The impact is due to the oscillation of the atoms deep within the solid object from which the images come. And whatever presentation we receive by direct contact—whether it is with the mind or with the sense organs, and whether it is the shape that is presented or other accidents—this presentation is the shape of the solid thing itself and is due either to a close coherence of the image as a whole or to a mere remnant of its parts. Falsehood and error, therefore, are always based on judgment added to a presentation that awaits confirmation or, at least, no contradiction. In the latter case, the presentation remains unconfirmed or even contradicted.[vi]

[51] So it is that the mental images we receive (even as mirrors receive images)—whether they arise in our sleep, or whether they are perceived by some other apprehension or perception of the mind or by one of the other criteria of judgement—these mental images would never have resembled what we call real and true things if we had not first come into contact with certain actual things. On the other hand, error would not have occurred if we had not experienced some other movement in ourselves conjoined with, but distinct from, the apprehension or perception of what is presented. Falsehood results from this movement—if it is not confirmed or if it is contradicted. By contrast, if it is confirmed, or if it is not contradicted, then truth is the result.

[52] We must closely adhere to this view so that the criteria of judgment based on clear and distinct perceptions will not be annulled, and so that we will avoid throwing all these things into confusion by maintaining falsehood as if it were the truth.

Hearing The next point. Hearing takes place when a current passes from the object—whether a person or something else—that emits voice or sound or noise, or produces the sensation of hearing in any way whatsoever. This current is broken up into homogeneous particles, which simultaneously preserve a certain mutual connection and a distinctive unity that extends back to the object that emitted them. This current, then, causes the perception of the external object in most cases, or, at the very least, it indicates its presence. [53] And without the transmission of this mutual connection and distinctive unity, no sensation such as this could arise. Therefore, we must not suppose that the air itself is molded into some shape by means of the emitted voice or something similar—for it is hardly the case that the air is acted upon by voice in this way. Instead, the blow that is struck in us when we utter a sound causes such a displacement of particles that it produces a current resembling breath. And this displacement gives rise to the sensation of hearing.

Smelling Moving on, we must believe that smelling, as with hearing, would produce no sensation without particles moving from the object—the right kind of particles that excite the organ utilized in smelling—some bringing confusing and unfamiliar smells, while some carry familiar smells without any confusion.

Atoms—Qualities, Parts, and Motion

[54] Moreover, we must hold that the atoms in fact possess none of the qualities belonging to things that appear to us except shape, weight, and size, and whatever is necessarily associated with shape. For every quality changes, but the atoms do not change since, when the composite bodies are dissolved, there must necessarily be a permanent something, solid and indissoluble, left behind that makes change possible. I do not mean change into or from the non-existent. Rather, I mean that change which happens most often by means of different arrangements and sometimes through the addition or subtraction of atoms. Therefore, these somethings that can be diversely arranged must be indestructible, exempt from change, while retaining their own distinctive bulk and shape. These, at the very least, must remain. [55] We see a similar case with what we experience every day. When things fall apart, we can more often than not recognize the shape of the parts that remain of the thing, whereas the thing’s qualities vanish. So it is that what is left behind at the dissolution of a body is sufficient to account for the differences in composite bodies. As I said, something must remain and be immune from destruction.

Furthermore, you should not suppose that the atoms have any and every size—or you may be contradicted by phenomena. Rather, we must admit differences of size in order to make it easier to explain our feelings and sensations. [56] But I repeat—it is not necessary to attribute every magnitude to atoms in order to explain qualitative differences. Anyway, if atoms came in all sizes, then we would have by now encountered an atom large enough to see. But we have never observed this—nor can we conceive how an atom could become visible.

Besides, you must not suppose that there are an unlimited number of parts, no matter how small, in any finite body. And so, we must reject as impossible the unlimited cutting and division of a finite body into smaller and smaller parts. For to go down such a path would result in reducing everything to nothing. In that case, we would be forced to admit that the existent things that make up compound bodies—which is to say, atoms—can be reduced to non-existence. Furthermore, no finite body can be transformed again and again ad infinitum into smaller and smaller parts. [57] It is impossible to imagine how a finite body would remain limited in size if we posit that an infinite number of particles, however small, are contained in the body. For clearly this infinite number of particles would have some size. And so, whatever size these particles have in themselves, the total amassed body they make would be infinite. Moreover, since what is finite has an extremity, or a limiting edge, that is distinguishable—even if this extremity is not by itself observable—we necessarily think of another such extremity next to or besides the first limiting edge. Considering matters in this way, we can proceed in thought from one limited thing to another until we arrive at infinity.

[58] We must understand that the minimum part or thing perceptible by sense does not correspond to that which can be traversed. Nor is it utterly unlike such a thing. It has something in common with things that can be traversed, though it does not have parts. But when, thanks to the illusion created by this commonality, we think we see another part in the minimum thing—a part on one side and another part on the other side—we must actually be seeing another minimum thing equal to the first. In point of fact, we see minimum things one after another, beginning with the first minimum thing. We do not observe them as occupying the same space nor as touching one another’s parts with their own parts. Rather, as unitary indivisibles they provide a means of measuring magnitudes. If the measured magnitude is greater, there are more of them. If smaller, then less.

[59] We must recognize that this analogy also holds for the minimum in the atom. It is only in the atom’s scale of size—that is, the atom’s very small size—that it differs from that which is observed by sensation. Still, it follows the same analogy. We have declared that atoms have magnitude based upon the analogy of things within our experience. And this magnitude, as small as it is, we have merely reproduced on a larger scale. Furthermore, the least and simplest things—that is, uncompounded things—must be regarded as extremities of lengths. As a unity, they provide the means for measuring lengths, whether greater lengths or smaller. This sort of measurement is accomplished by means of mental vision since direct observation is impossible. For the similarity that exists between the minimum in the atom and minimum things perceptible to sense is sufficient to justify the conclusion so far as it goes. But it is not possible that the smallest parts of the atom group themselves together through the possession of motion.

[60] Further, we must not assert up or down of that which is infinite or unlimited as if there were a zenith or nadir, that is, a highest or lowest point. As for the space overhead, however, if it is possible to draw a line to infinity from the point where we stand, we know that this space will never appear to us to be at the same moment up and down with reference to the same point (the point where we stand). The same goes for the space below the hypothetical standpoint and the same kind of infinite line. Judging that it is both up and down at the same moment with reference to the same point is inconceivable. Therefore, it is possible to assume one direction of motion that we conceive as extending upward without limit, and another direction that we conceive as downward, even if our upward motion from our beginning point reaches the feet—or downward motion—of those above us, or our downward motion reaches the heads—or upward motion—of those below us. Nonetheless, the whole of the motion in each case is conceived as extending in opposite directions ad infinitum.

[61] Atoms necessarily move with equal speed when travelling through the void without meeting resistance. Heavy atoms will not travel quicker than small and light ones—assuming nothing encounters them. Nor will small atoms travel quicker than large ones if they find a passage suitable to their size, and if they are not obstructed in their movement. Nor will their upward or their lateral motion, which is due to collisions, nor their downward motion, which is due to weight, affect their speed. As long as there is either motion, it must continue at a speed as fast as thought itself as long as there is no obstruction, whether due to external collision or to the atom’s own weight in counteracting the force of the blow.

[62] Furthermore, in composite bodies, one atom will travel faster than another, although their atoms have equal speed. This is because the atoms in the aggregates are travelling in one direction during the shortest continuous time, even though they move in different directions in times so short as to be appreciable only by reason, but frequently collide until the continuity of their motion is appreciated by sensation. For the assumption that beyond the range of direct observation even the minute times conceivable by reason will present continuity of motion is not true in the case before us. Our canon is that direct observation by sense and direct apprehension by the mind are alone invariably true.

The Soul—Its Nature and Role in Sensation

[63] Next, keeping in view our sensations and feelings—since in this way we will have the surest grounds for confidence—we must generally recognize that the soul is a bodily thing composed of fine particles dispersed throughout the whole assemblage of atoms in the human organism.

The soul most nearly resembles wind with an admixture of heat. It is like wind in some ways and heat in others. But there is the third part that exceeds the other two in the fineness of its particles and thereby keeps in closer touch with the rest of the human organism. This is shown by the powers of the soul, its feelings, the ease with which it moves, its thought processes, and by all those things we lose when we die.

We must keep in mind that the soul has the greatest share in causing sensation. [64] Nevertheless, if it had not been somehow confined within the rest of the human organism, it would not have had sensation. Still, the rest of the human organism has its own soul-derived share of the ability—even though it provides the indispensable condition for the soul. And yet it does not possess all the properties of the soul. And so, on the departure of the soul it loses sensation. This is so because it does not have this power in itself. Rather, something else that came into being with it supplied it to the body. This other thing—through the power actualized in it by means of motion—at once acquired for itself the property of sense perception. And because of its proximity to and affinity with the body, this other thing imparted it, as I said, to the body.

[65] Hence, as long as the soul is in the body, it never loses sensation through the removal of some other part. The container may be dislocated in whole or in part, and portions of the soul may thereby be lost. Despite this, the soul will nevertheless retain sensation if it manages to survive. But as soon as those atoms that make up the nature of the soul have departed—however few—the rest of the human organism no longer has sensation, whether the whole of it survives or only a part. Moreover, when the whole of the human organism is broken up, the soul is scattered and no longer has the same powers as before, nor the same motions. Therefore, the soul no longer possesses sensation.

[66] This is so because we cannot think of the soul as sensing without it being in this composite whole and moving with these movements. Nor can we think of it in this manner whenever the containers that enclose and surround it are not the same as those in which the soul is now located and in which it performs these movements.[vii]

[67] There is another point we must consider—the nature of that which is without a body, which is to say incorporeal. According to the way people now use the term incorporeal, it can be thought of as self-existent. But aside from the void, it is impossible to think of anything incorporeal as self-existent. And the void itself is able neither to act nor be acted on, but it simply allows bodies to move through it. Therefore, those who call the soul incorporeal speak foolishly. For if the soul were incorporeal, it would be able neither to act nor be acted on. As it is, however, both these properties manifestly belong to the soul.

[68] If, then, we bring all these arguments concerning the soul to the criteria of our feelings and sensations, and if we keep in mind the proposition stated at the beginning, we will see that the subject has been adequately set out in outline. This will enable us to determine the details with accuracy and confidence.

Properties and Accidents[viii]—Including Time

Moving on, the shapes, colors, magnitudes, and weights—in short, all those things that are predicated of body as accidents either of all things or of visible things—are knowable by sensation itself. We must not think of these as existing independently in themselves—for that is inconceivable—[69] nor as being non-existent, nor as being some other and incorporeal entity inhering in the body, nor again as being parts of it. We must hold that the whole body in a general way derives its permanent nature from all these—though the body is not, as it were, formed by grouping these together in the same way that a larger aggregate is made up from the particles themselves, whether these particles be primary or any magnitudes whatsoever less than the whole aggregate. All these, I repeat, merely give the body its own permanent nature. They all have their own characteristic modes of being perceived and distinguished—but always along with the whole body in which they inhere, and never apart from it. It is on account of this complete conception of the body as a whole that it is designated body.

[70] Properties often attach to bodies without being permanent aspects. These are neither invisible nor incorporeal. Therefore, using the term as it is commonly used, we make it clear that these properties do not have the nature of the whole thing to which they belong (that which, conceiving it as a whole, we give the name of body), nor do they have the nature of the permanent aspects without which we cannot think of a body. And because of certain peculiar modes of apprehension into which the complete body always enters, each of them can be called by this name—[71] but only as often as they are seen actually to belong to it, since such properties are not permanent aspects. There is no need to banish from reality the clear evidence that these properties do not have the nature of that whole—by us called body—to which it belongs, nor of the permanent aspects that accompany the whole. Nor, on the other hand, must we suppose that they have independent existence (for this is just as inconceivable in their case as in the case of the permanent accidents). But—as is manifest—they should all be regarded as properties of bodies rather than as permanent aspects that accompany bodies. Nor do they independently exist. Rather they are seen to be exactly as and what sensation itself makes them individually claim to be.

[72] There is another point we must consider carefully. We must not investigate time as we do the other things that we investigate in an object, namely, by referring them to the preconceptions envisaged in our minds. Rather, we must take into account the clearly perceived phenomenon by which we speak of time as long or short, linking it closely to our experience. We do not need to adopt any novel terms as preferable, but we should employ the usual expressions in reference to time. Nor do we need to predicate anything else of time as if this something else contained the same essence as is contained in the proper meaning of the word time. This, after all, is done by some. We must chiefly consider what we associate with time and that by which we measure time. [73] The matter requires no further demonstration. We need only to reflect on the fact that we associate time with days and nights and their parts, and similarly to feelings and the lack of feelings, and to states of movement and states of rest. And so, we understand that a distinct property of these is what we call time.[ix]

The Rise of Other Worlds 

and the Evolution of Human Languages

In addition to the foregoing points I have made, we should consider that the worlds and every other finite aggregate that bears a strong resemblance to things we commonly see have come into being out of the infinite. All these, whether great or small, have been separated off from distinct gatherings of atoms. And all things will be dissolved again—some faster, some slower, some through the action of one set of causes, others through the action of another set.[x][74] Moreover, we must not suppose that the worlds necessarily have one and the same shape.[xi] For no one can demonstrate that in one sort of world there might not be contained the seeds out of which animals and plants arise, as well as everything else we see, whereas in another sort of world there could not possibly be these seeds.[xii]

[75] Again, we must suppose that human nature was compelled by circumstances to learn many things of different kinds. And reason subsequently developed what it had received and made additional discoveries. The developments moved along at a quicker pace among some peoples and at a slower pace among others. So it was that the progress made at times was great, and at other times less so.

Therefore, even the names of, or words for, things did not originally spring into being thanks to convention. Instead, each unique ethnic group of human beings produced them when they were affected by distinct feelings and received distinct apparitions. The air emitted in this way was shaped by these distinct feelings and apparitions, and in different ways depending on the variety of lands inhabited by the different groups of people. [76] Subsequently, whole ethnic groups adopted their own special terms so that their communications might be less ambiguous to one another and more briefly expressed. As for things not generally known, or things unseen, those who were aware of them tried to introduce these things by circulating certain terms for them. These names were either instinctively uttered sounds spoken under a kind of compulsion, or they were selected in a more rational fashion, based on analogy and according to general usage.

How to Understand Heavenly Phenomena 

So as to Avoid Fear and Anxiety and Be at Peace

Moving on, as for things in the sky, we should acknowledge that revolutions and solstices and eclipses and risings and settings and the like take place without the administration or command, either now or in the future, of some being that simultaneously enjoys perfect bliss as well as indestructibility. [77] This is so because practical troubles and anxieties and feelings of anger and the granting of favors do not accord with bliss, but always imply weakness and fear and dependence upon one’s neighbors. Nor should we hold that these things in the sky, which are no more than globular masses of fire, enjoy bliss or that they assume these motions at will. No, in every term we use, we must hold fast to all the majesty that attaches to such notions. Otherwise, the terms will generate opinions inconsistent with this majesty, and such inconsistency will be enough to produce the most disturbing confusion in our souls. Therefore, where we find regularly recurring phenomena, we must assign the regularity of the recurrence to the original interception and conglomeration of atoms by which the cosmos was formed.

[78] Furthermore, we must hold that the function of the study of natural phenomena is to clearly understand the cause of the most important things. And we must hold that blessed happiness depends on this, and on knowing what the heavenly bodies really are, and any similar knowledge that would contribute to a clear understanding. Moreover, relative to such points as these, we must recognize that there is no plurality of causes or contingency. Rather, we must hold that nothing suggestive of conflict or disturbing confusion is compatible with an indestructible and blessed nature. The mind can grasp the simple truth of this.

[79] But when we come to subjects for special inquiry, there is nothing in the knowledge of risings and settings and solstices and eclipses and every similar subject that contributes to our blessed happiness. On the contrary, those who know about such matters, while remaining ignorant about the true nature of the heavenly phenomena or the most important causes, feel just as much fear as those who do not have special knowledge. Actually, it is possible to say that they feel an even greater fear when the feeling of astonishment stirred up by this additional knowledge cannot find a solution or understand how these phenomena depend on the highest causes.

Therefore, if we discover more than one cause that may possibly account for solstices, settings and risings, eclipses, and the like, even as we also found in particular matters of detail, [80] we must not suppose that our treatment of these matters fails in terms of accuracy—as far as accuracy is required to ensure our tranquility and blessed happiness, anyway. When, therefore, we investigate the causes of celestial and atmospheric phenomena—as with all that is unknown—we must take into account the variety of ways in which analogous occurrences happen within our experience. We must disregard those who, overlooking the fact that these objects are only seen at a distance, do not recognize the difference between that which is or comes about from a single cause and that which may be the effect of any one of several causes. We must also disregard those who are ignorant of what makes tranquility possible or what prevents it. If, then, we suppose that an event could happen in one particular way or another out of many, then we will be just as tranquil as if we knew with certainty that it happened in one particular way.

[81] There is yet one more point to grasp—namely, that the greatest disturbance arises in the human soul thanks to the belief that the heavenly bodies are blessed and indestructible, while these same bodies simultaneously wish and act and cause in ways that are incompatible with these attributes. Disturbances also arise thanks to the anticipation or suspicion of some everlasting evil—either because of the myths or because we are in dread of the mere insensibility of death, as if it had to do with us. People are reduced to this state not because of conviction but because of a certain irrational tendency. Accordingly, if men do not set limitations on their terror, they must suffer as much or an even more intense anxiety than the man whose views on these matters are quite vague. [82] But mental tranquility means being released from all these troubles and keeping in mind the general and most important points.

Therefore, we must attend to present feelings and sensations, whether those of mankind in general or those peculiar to the individual. We must also attend to all the clear evidence available to us as given by each of the criteria. By paying attention to these, we will correctly and fully be able to explain the source of the disturbance and the fear, banishing it by accounting for celestial phenomena and for all other things that happen to us from time to time—things that cause the utmost fear in the rest of mankind.

Conclusion

Here then, Herodotus, are the most important points on the whole of nature in summary form. [83] Accordingly, if this statement is accurately retained and the points herein take effect, then I believe that a man will be far better equipped than others—even if he never goes into all the exact details. This is so because he will clear up for himself many of the points that I have worked out in detail in my longer and more complete treatise. The summary will help if one keeps it in mind. It is such that those who are already more or less, or even perfectly, acquainted with the details can, by breaking down what they know into such elementary perceptions as these, successfully pursue their research into the whole of nature. At the same time, those who are not as advanced can silently fashion and as quick as thought run through the teachings most important for the calming of the mind.

__________

DIOGENES LAERTIUS: Such is Epicurus’ letter on natural things. Next is his letter on things in the sky.

Notes

[i] At some point a scholiast, or commentator, added the following (from now on such commentary will simply be noted as “Added commentary:”): “He says this also in the Larger Epitome near the beginning and in the first book of On Nature.”

[ii] Added commentary: “He repeats this in the first book of On Nature and in books 14 and 15 of the Larger Epitome.”

[iii] Added commentary: “For neither does the divisibility go on without end, he says below. And, he adds, since the qualities change, unless one is prepared to keep enlarging their magnitudes also simply without end.’”

[iv] Added commentary: “He further says below that the atoms move with equal speed since the void makes way for the lightest and heaviest alike.”

[v] Added commentary: “He says below that atoms have no quality at all except shape, size, and weight. He states that color varies with the arrangement of the atoms in his Twelve Rudiments. He further says that atoms are not of any and every size. Anyway, no atom has ever been seen by our sense perception.”

[vi] Added commentary: “Following a certain movement in ourselves connected with, but distinct from, the mental picture presented―which is the cause of error.”

[vii] Added commentary: “He says elsewhere that the soul is composed of the smoothest and roundest of atoms, far superior in both respects to those of fire. He says that part of the soul is irrational, this part being scattered over the rest of the frame, while the rational part resides in the chest, as is manifest from our fears and our joy. He says that sleep occurs when the parts of the soul that have been scattered all over the composite organism are held fast in it or dispersed, and afterwards collide with one another by their impacts. The semen is derived from the whole of the body.”

[viii] Though others (R.D Hicks, Eugene O’Connor, George Strodach) over the past century have translated sumptōma and sumbebēkos alternatively, and sometimes oppositely, to what we give here, and despite the apparent confusion of Liddell & Scott’s Greek-English Lexicon, we at the Cave have followed the recent and consistent scholarship of Lloyd P. Gerson (and sometimes Brad Inwood with others) in giving sumptōma as “property” and sumbebēkos as “accident.” That said, the translation does not always seem to work, though the general sense is usually clear.

[ix] Added commentary: “He says this both in the second book of On Nature and in the Larger Epitome.”

[x] Added commentary: “It is clear, then, that he also makes the worlds perishable, as their parts are subject to change. Elsewhere he says the earth is supported on the air.”

[xi] Added commentary: “On the contrary, in the twelfth book of On Nature, he himself says that the shapes of the worlds differ, some being spherical, some oval, others again of shapes different from these. They do not, however, admit of every shape. Nor are they living beings that have been separated from the infinite.”

[xii] Added commentary: “And the same holds good for their nurture in a world after they have arisen. And so too we must think it happens upon the earth also.”