Welcome to Episode One Hundred Thirty-Three of Lucretius Today. This is a podcast dedicated to the poet Lucretius, who wrote “On The Nature of Things,” the only complete presentation of Epicurean philosophy left to us from the ancient world. I am your host Cassius, and together with our panelists from the EpicureanFriends.com forum, we’ll walk you through the ancient Epicurean texts, and we’ll discuss how Epicurean philosophy can apply to you today. We encourage you to study Epicurus for yourself, and we suggest the best place to start is the book “Epicurus and His Philosophy” by Canadian professor Norman DeWitt. If you find the Epicurean worldview attractive, we invite you to join us in the study of Epicurus at EpicureanFriends.com, where you will find a discussion thread for each of our podcast episodes and many other topics. Today we complete our discussion of Epicurus’ Letter to Pythocles. Now let’s join Joshua reading today’s text:
Comets occur either when fire is collected together in certain regions at certain intervals of time in the upper air because some gathering of matter takes place, or when at certain intervals the heaven above us has some peculiar movement, so that stars of this nature are revealed, or when they themselves at certain seasons start to move on account of some gathering of matter and come into the regions within our ken and appear visible. And their disappearance occurs owing to the opposite causes to these.
 Some stars ‘revolve in their place’(as Homer says), which comes to pass not only because this part of the world is stationary and round it the rest revolves, as some say, but also because a whirl of air is formed in a ring round it, which prevents their moving about as do the other stars: or else it is because there is not a succession of appropriate fuel for them, but only in this place in which they are seen fixed. And there are many other ways in which this may be brought about, if one is able to infer what is in agreement with phenomena.
 That some of the stars should wander in their course, if indeed it is the case that their movements are such, while others do not move in this manner, may be due to the reason that from the first as they moved in their circles they were so constrained by necessity that some of them move along the same regular orbit, and others along one which is associated with certain irregularities: or it may be that among the regions to which they are carried in some places there are regular tracts of air which urge them on successively in the same direction and provide flame for them regularly, while in other places the tracts are irregular, so that the aberrations which we observe result.
But to assign a single cause for these occurrences, when phenomena demand several explanations, is madness, and is quite wrongly practiced by persons who are partisans of the foolish notions of astrology, by which they give futile explanations of the causes of certain occurrences, and all the time do not by any means free the divine nature from the burden of responsibilities.
 That some stars should be seen to be left behind by others is caused because though they move round in the same orbit they are carried along more slowly, and also because they really move in the opposite direction though they are dragged back by the same revolution: also because some are carried round through a greater space and some through a lesser, though all perform the same revolution. But to give a single explanation of these occurrences is only suitable to those who wish to make a show to the many.
 What are called falling stars may be produced in part by the rubbing of star against star, and by the falling out of the fragments wherever an outburst of wind occurs, as we explained in the case of lightning-flashes: or else by the meeting of atoms productive of fire, when a gathering of kindred material occurs to cause this, and a movement in the direction of the impulse which results from the original meeting; or else by a gathering of wind in certain dense and misty formations, and its ignition as it whirls round, and then its bursting out of what encloses it and its rush towards the spot to which the impulse of its flight tends. And there are other ways in which this result may be brought about, quite free from superstition.
The signs of the weather which are given by certain animals result from mere coincidence of occasion. For the animals do not exert any compulsion for winter to come to an end, nor is there some divine nature which sits and watches the outgoings of these animals and then fulfills the signs they give.
 For not even the lowest animal, although ‘a small thing gives the greater pleasure,’ would be seized by such foolishness, much less one who was possessed of perfect happiness.
All these things, Pythocles, you must bear in mind; for thus you will escape in most things from superstition and will be enabled to understand what is akin to them. And most of all give yourself up to the study of the beginnings and of infinity and of the things akin to them, and also of the criteria of truth and of the feelings, and of the purpose for which we reason out these things. For these points when they are thoroughly studied will most easily enable you to understand the causes of the details. But those who have not thoroughly taken these things to heart could not rightly study them in themselves, nor have they made their own the reason for observing them.