Notes

1 In our own country Dr. Masson (Lucretius: Epicurean and Poet) has recently written a very suggestive, though not always accurate, sketch of Lucretius’s relations to his predecessors and to modern scientific ideas, and has most successfully represented the spirit of the poem.

1 There is, as a matter of fact, considerable doubt whether Democritus attributed weight to the atoms, but I am inclined to believe that he did.

1 Galen, de med. emp. 1259, 8; Diels B. 125. Democritus’s exact position is very difficult to make out, but it seems that he accepted the evidence of the senses for the primary properties, size, shape, and weight, but regarded it with suspicion for all other qualities: in other words he held that touch alone among the senses could be trusted.

1 Two lines are probably lost here, the sense of which has been admirably restored by Munro:

corporibus, quod iam nobis minimum esse videtur, debet item ratione pari minimum esse cacumen 1 Read mussant and place semicolon after purum, 1. 658.

1 Lambinus supplied the sense of a missing verse: et nervos alienigenis ex partibus esse. 1 Two lines seem to be lost here, of which Munro has supplied the sense:

ex alienigenis, quae terris exoriuntur. sic itidem quae ligna emittunt corpora, aluntur 1 Munro again has well supplied the sense of two lost lines:

sed spatium supra docui sine fine patere. si finita igitur summa esset materiai, 1 The next eight lines are omitted or mutilated in the MSS., but once more Munro’s restoration must give the sense, and probably something very near the actual words.

1 The best MS. marks eight lines lost here, corresponding to the mutilation above: the words in brackets would give the general sense, as suggested by Munro.

1 Read with Munro, et ecum vi.

2 Read with Munro, ornatasque armis statuas.

1 A considerable number of lines seems to be lost here, in which Lucretius probably first gave other reasons for the atoms’ velocity, and then fulfilled the promise of line 62 to explain how the atoms by their motion created and dissolved things: the next two lines read like a conclusion of such a section.

2 A line is probably lost here, of which Hoerschelmann has restored the sense: corpora sponte sua volitare invicta per aevum.

1 Read sensus for sese with Bernays.

1 This should be the sense, but the reading is uncertain: possibly quaerit.

1 The text is corrupt and a line is probably lost: the translation follows Brieger’s restoration:

ventis differri rapidis, nostrisque veneno sensibus esse datum, 2 It is likely that a paragraph is here lost in which Lucretius showed that the size of the atoms was limited: otherwise some would be perceptible. To this he probably refers in lines 479, 481 and 499.

1 Again it is likely that some lines are lost in which Lucretius stated the general argument that if variety of shapes in the atoms were infinite, all extremes in our experience would be far surpassed: he then proceeds to illustration.

1 This is the sense, though the text is uncertain.

2 Reading ostendens with Munro.

1 A line is lost, of which this must have been the general sense.

1 A line is lost here, of which this was the probable sense.

1 A line is lost, of which this must have been the sense.

1 It is impossible to make sense of the passage as it stands, and Giussani is probably right in supposing several verses lost, in which the poet said that only such things could give anything off as contained void, and then gave a list of examples, ending up with the cetera of line 859.

1 Giussani may be right in thinking that we should read latices (water) instead of lapides (stones), as it suits better with what follows.

1 A line is lost, which might have been of the form hi proprii sensus mortalia semina reddunt.

1 Read capulum with Vossius.

1 The reading is uncertain, but may have been e summa … sede.

1 A line is lost, of which this must have been the general sense.

1 The MSS. are corrupt, but this must have been the sense.

1 i. e. forces us to conclude that it is they which see.

1 The text is uncertain, but this was probably the meaning.

1 The text is uncertain, but the sense probably this.

1 There may be a verse lost here, or else the construction is slightly careless.

1 Reading truncum for utrumque, but the text is uncertain.

1 A line is lost, of which this was probably the sense.

1 Bernays’ suggestion gnatis seems the best of many proposals.

1 Some lines are lost here.

1 Translating Munro’s suggestion patrum coetumque decorum.

1 We may fill in the sense of the immediately succeeding lines with certainty, but a long passage has been lost, probably of about 50 lines.

1 At least one line is lost here.

1 A line has probably been lost, such as hoc illis fieri, quae transpiciuntur, idemque.

1 Read, with I. Vossius, et reboat raucum Berecyntia

2 Read, with Bernays, et gelidis cycni nocte oris

1 The text is uncertain, but this must be the general sense.

1 This section seems misplaced, and should possibly come before the preceding paragraph.

1 This must be the sense, though the text is uncertain.

1 The end of the line has been ousted by an intrusion from the next: the sense was probably this, as Munro suggests.

1 It is impossible to replace with certainty the mutilated word.

1 A line is lost, of which the words in brackets give the general sense.

1 The line is corrupt, and I have translated Munro’s correction: quaerere proporro sibi sene senescere credas.

1 This paragraph seems misplaced: but it is not clear where it should come in (possibly after the next paragraph), and it may be a subsequent addition, which the poet did not properly work into its context.

1 A line is lost, of which this was possibly the sense.

1 The text is uncertain, but this must have been the general sense.

1 A line is lost, of which this was probably the sense.

1 This and the next two paragraphs seem rather out of place here: possibly they should be placed before the preceding paragraph, or else they may be a later addition by the poet.

1 These six lines were probably written by the poet as a later addition.

1 Two words at the end of the line are corrupt: puppibus or navibus must have been the first.

1 Two or more lines must here be lost.

2 Read exsistant, placentur et omnia rursum quae furerent.

1 The last word of the line is uncertain.

1 Translating Lachmann’s nimbis for montis.

1 The text is uncertain, but this seems to be the sense.

1 Either this paragraph is a disconnected fragment, or more probably something has been lost before it, introducing a new section of the paradoxes of nature on earth.

1 A line is lost, of which the words in brackets give the probable sense.

1 Reading forte his for poteis with Munro.

2 Reading tractu with Polle.

1 The reading is extremely uncertain: Heinrichsen’s suggestion membra domans percepit fervida fabris may be right.

1 A considerable passage is lost, in which the poet passed to a quite new subject.

1 The MS. reading caeli lorica is probably quite right, and a line is lost, of which this, as Giussani suggests, was probably the sense.

1 Place; after partes and, after superne.

1 The MS. text involves an impossible false quantity, but this must be the sense: possibly, as Housman suggests, the order of the words is wrong.

1 Some lines of connexion seem to be lost here.

1 ff. The introductory invocation to Venus has caused great trouble to the commentators, as it appears to be inconsistent with Lucretius’s belief (e. g. II. 646) that the gods live a blessed life apart, and have no concern with the government of the world or the affairs of men. But, though to some extent, no doubt, such an invocation is to be accepted as a poetical tradition, it is much more truly explained as having for Lucretius an esoteric meaning. Venus is to him the creative power of nature, the life-giving force, Lucretius’s reverence for which may fairly be regarded as his true religion. (See Martha, Le poème de Lucrèce, pp. 61 ff.)

41. in our country’s time of trouble. The poem was published after Lucretius’s death in 55 bc, and its unfinished state shows that he must have been working at it in the immediately preceding period. During that time Caesar was fighting in Gaul, but Lucretius is more probably thinking of the gathering storm of civil war.

42. Memmius’s noble son. C. Memmius, to whom the poem is addressed, was an aristocratic contemporary of Lucretius. He had taken some part in public life, and seen foreign service, but was better known as a prominent and somewhat dissolute figure in society, and a patron of letters. He was probably a professed Epicurean, whom Lucretius wished to arouse to a more real faith and a better understanding of Epicurus’s doctrines.

43. a man of Greece: of course Epicurus, whom Lucretius only once mentions by name (III. 1042). See Introduction, pp. 10 ff.

44. the fiery walls of the world. Lucretius conceived of our world as a sphere, of which the outer coat was a circling stream of fiery ether (V. 457-70). The expression here is then to be taken quite literally.

45. Even as at Aulis, &c.: for the story of the sacrifice of Iphigeneia at Aulis in order to procure favourable winds for the fleet starting against Troy, see Euripides’ play, from which Lucretius has borrowed several details, and even translated phrases in this passage.

46. the Virgin of the Cross-roads, i. e. Artemis.

47. seized by men’s hands, &c. Iphigeneia was brought to Aulis on the understanding that she was to be married to Achilles. Lucretius, therefore, here carefully selects phrases which would remind a Roman reader of the ceremonials of marriage.

48. our own Ennius. C. Ennius (died 169 bc), the first great genius in Latin poetry, who introduced the hexameter, and laid the foundation of nearly all the later branches of Roman poetry. He believed in Pythagoras’s theory of metempsychosis, and thought that he himself was possessed by the soul of Homer, whose appearance to him in a vision he described in one of his Saturae.

49. nothing is ever begotten of nothing. This first principle shows that the ultimate basis of the universe is a store of matter, to which no addition is ever made. Lucretius’s ‘proof’ has been much criticized on the ground that he argues against ‘spontaneous’ creation by a denial of ‘sporadic’ creation. But to his mind they were really the same: if things came into being without a ‘seed’ or cause, the effect would be that they would appear to spring from alien sources, man from the sea, &c. As this does not occur, we may be sure that things are never created without a ‘seed’, i. e. are never uncaused additions to matter. Notice that his proof also establishes the law of cause and effect, which was his strongest weapon of attack on religion.

50. nor does she destroy ought into nothing. The second principle is complementary to the first. As matter never receives any addition, so it never suffers any loss: the two together constitute the modern notion of the permanence of matter, and show its existence in the form of particles. Note again the proof: if nature could destroy anything, the whole universe would perish, because (as he explains more clearly in lines 556 ff.) the process of destruction is quicker than that of creation.

51. there is void in things. Having established the existence of matter in the form of particles, he proceeds to show that there must also be empty space. To Epicurus’s argument that without it motion is impossible, he adds two others derived from the nature of compound things.

52. which some vainly imagine, i. e. the Stoics. When Lucretius alludes to opponents vaguely, without mentioning their names, he nearly always has in view his natural rivals, the Stoics (e. g. I. 465, 1053). They held that void did not exist, but that motion was due to the mutual interchange of places between things—a view not unlike that which is now held in conjunction with the conception of ether. Lucretius replies that such interchange of place necessarily implies empty space.

53. But if by chance any one thinks. The argument here is rather obscure: ‘this comes to be’ is the filling up of the interval between the two bodies with air. Lucretius imagines a view of air as a kind of elastic fluid, which condenses, as the bodies meet, and then expands again when they separate. To it he objects that such condensation and expansion itself implies an admixture of empty space: a thing can only expand because there is more vacuum in it, or contract because there is less.

54. Even so time exists not by itself … Once more the argument is difficult. The Stoics, against whom Lucretius is, as usual, disputing, held that time was an existence in itself, and even went so far as to call it a ‘body’. Lucretius replies that it is only a sensation that we get from things, an ‘accident’ of things, just as much as their colour or scent or sound, or wealth or poverty.

55. Then again, when men say. . . The Stoics had apparently raised a special difficulty with regard to Epicurus’s theory of ‘accidents’ in the case of events in the past: the Trojan War, they said, is something of which we are conscious now, but all the persons, of whom you say it was ‘an accident’, are long since dead, and we are not conscious of them, much less could we be of their ‘accidents’. Lucretius’s reply is twofold: he says first, in a rather frivolous spirit: ‘Well, we can say that it is an “accident” of the place, or if you object that that too has changed, of that part of space.’ Secondly, he replies seriously: ‘of course it was an “accident” of the persons, for, if they had not existed, neither could the Trojan War and its events.’

56. Again, if nature had ordained … an argument which is more obscure than it looks at first sight. Let us suppose that the rate of destruction is twice as quick as that of creation, and that it takes, e. g. ten years for a horse to be conceived, born, and come to maturity, starting from particles the size of the Lucretian atom: it will then require five for him to grow old and die, and dissolve again into the particles. If at the end of the twentieth year, nature requires to make another horse, the Lucretian atom would, so to speak, be there ready, having lain dormant for five years. But if there is no limit to destruction, during those five years the process of destruction will have been going on at an equal rate, and it will now require not ten but twenty years to put the particles together into a horse: and the next generation would require forty, and so on, creation never keeping pace with destruction. But, as it is, we see that there are fixed periods in which things can be created and come to maturity: there must then be a limit to destruction; in other words, there are ‘atoms’ (ἄ-τομοι, indivisible things). (This explanation and illustration come from Giussani’s edition of Lucretius.)

57. since there are extreme points … Another difficult proof of the complete solidity (and therefore indestructibility) of the atom. Lucretius is arguing, as Epicurus had taught him to do, from the analogy of perceptible things. If we try, e. g. to fix our attention on the extreme point of a needle, we can see a point so small that, though it is perceptible itself, it is the minimum for sight: if we tried to see half of it, it would pass out of the range of vision altogether. The needle itself is composed of a countless number of such tiny points. In the same way then the atom is composed of a few minute parts, which can only exist as parts of the atom, and could not be separated from it; they are the minimum of material existence, and can have no existence apart from the atom which they compose. The atom then has extension, but not separable parts: in other words, is perfectly solid.

58. Heraclitus of Ephesus (about 510 bc) held that the primary substance of which the world was created was fire, which gave rise to other things by a perpetual flux; everything was either streaming upwards to form fuel for the fire, or downwards to the moisture which lay at the other end of the ‘path’. Lucretius takes him as typical of the class of early philosophers who believed that the world was made of one element, and introduces ideas which were not actually in Heraclitus’s theory: e. g. the notion of rarefaction and condensation really comes from Anaximenes, who believed air to be the primary material. Lucretius’s argument holds well enough for any such theory; if you select one element as the basis, then, if it changes into other things, it ceases to exist as itself; or if it continues to exist, then other things do not.

59. Empedocles of Agrigentum (about 440 bc) is selected as the type of the philosophers who held that the world was composed of more than one element; he himself believed that it was made of all four, earth, air, fire, and water, all eternal and indestructible, but capable by combination and separation of forming the perceptible world. Lucretius again embraces in his criticism two schools of thought, those who held that the elements retained their nature in combination (770 ff.), and those who held that they ‘changed’ into other things (763 ff.). But his general criticism is just: on the one hand, Empedocles is too much of a pluralist, for by his four, always heterogeneous, elements he destroys the fundamental unity of the world; on the other, he is not enough of a pluralist, for the four elements are not sufficient to account for the infinite variety of phenomena.

60. that island, i. e. Sicily.

61. scarce born of human stock. Empedocles, who practised magic, seems to have laid claim to divine powers.

62. the homoeomeria of Anaxagoras of Clazomenae (about 440 bc), who held a theory which was an advance on that of the earlier philosophers, whom Lucretius criticizes, and really paved the way for atomism, but Lucretius has not understood him. He held, in the first place, that things were composed of ‘seeds’, small particles like in substance to the whole. But, as Lucretius points out, this will not account for the phenomena of change, which it was, in fact, Anaxagoras’s chief aim to explain. For this purpose he said indeed that ‘there is a portion of everything in everything’, but explained that these ‘portions’ were not merely extremely minute, but ‘only perceptible by reason’, i. e. we know that they are there, but never could see them. He came, in fact, near to the modern conception of chemical change, and the crude criticism of Lucretius from line 875 onwards is therefore beside the mark.

63. Moreover, suppose now, &c. This proof by imaginary experiment of the infinity of the universe is a famous one. It is used in much the same form by Locke, Essays II. 13.

64. Herein shrink far from believing, &c. This theory, held again by the Stoics, that all things tend to the centre of the world, came, as will be seen, very near the truth, and was an approach to the modern idea of gravitation. Lucretius could not, of course, adopt it, as it was a direct contradiction of the fundamental Epicurean theory that the natural motion of things was always downwards (II. 184 ff.).

65. the spaces of the Campus, i. e. the Campus Martius, just outside the walls of Rome, on which military reviews were held, and sometimes an army would be encamped. Munro notes that in 58 bc Caesar had his army there for three months before starting for Gaul, and this occasion may well be in Lucretius’s mind. Indeed, above, in lines 12 and 13, he seems to be thinking of the rivalry of Caesar and Pompey.

66. For since they wander through the void, &c. The account of the movement of the free atoms in the void is a little confused in this and the following passages. Lucretius really conceives of three causes of their movement: (1) the natural fall downwards due to their weight; (2) the occasional slight swerve sideways (216 ff.); (3) the movement due to the collisions originally brought about by this swerve. Here, rather illogically, he only mentions (1) and (3), as he is reserving his account of (2) owing to its special importance.

67. traces of a concept. See note on line 744.

68. such jostlings hint, &c. A very important passage for Lucretius’s theory of motion. All atoms are always moving at the full atomic speed (142 ff.), even in compound bodies, inside which, as they collide with one another, they accomplish tiny trajectories, each moving in the direction which the last blow gave it, until it collides with another atom, and is started in a new direction. This internal vibration in all directions will of course retard the motion of the whole, and we must imagine the atoms forming tiny molecules, and then slightly larger bodies, with ever lessening motion, until, when the bodies are large enough for us to perceive, such as the motes in the sunbeam, the motion is also sufficiently retarded to be visible to us. All this, though not clearly stated, is implied in these few lines.

69. Nor again do the several particles, &c. Here the idea of internal vibration and consequent retardation comes out very clearly; even the sun’s light is so impeded, as well as by the opposition of the air, through which it passes.

70. no bodily thing can of its own force, &c. This is again an important point: upward motion is always the result of external force. Even among the atoms it can only happen as the result of collisions, when e.g. one atom is squeezed between two others and thus shot up.

71. push a little from their path. The notion of the slight swerve of the atoms and its tremendous result in the free will of man is a supremely important point in the Epicurean philosophy, for it combats Democritus’s belief in complete determinism, which Epicurus regarded as a more dangerous enemy to morality than even religion. See Introduction, p. 17.

72. But if perchance any one believes. This paragraph contains one of Lucretius’s most acute pieces of reasoning, that in a vacuum all things fall at the same pace.

73. so that you see a start of movement, &c. The relation between the swerve of the atoms and man’s free-will is, of course, to Lucretius’s mind not a mere analogy: the former is the cause of the latter. The mind is composed of a subtle texture of fine atoms (III. 161 ff.), and it is the swerving of these atoms which gives rise to an act of will.

74. the barsh shuddering sound, &c. Sound, in Lucretius’s notion, is caused, just like sight or smell, by a body of particles given off by the object, and penetrating the ear (IV. 523 ff.).

75. For suppose the first bodies, &c. For this idea of the inseparable ‘least parts’ in the atom see I. 599 ff.

76. For because you see, &c. Here we meet a curious principle of Epicurus, which Lucretius nowhere states, but often acts on, of the ‘equal distribution’ (ἰσονομία) of things. If a certain class is rare in some parts of the world, or even in our world altogether, it will be found in plenty in other parts of the world or the universe: there is, on the whole, an equal number of things of the same kind. Compare 569 ff. for a similar idea.

77. the Great Mother of the gods. This was the title of the earth-goddess, Cybele, whose worship had been brought to Rome from Phrygia in 204 bc Lucretius in the next paragraph explains the ceremonial of the cult allegorically.

78. Then comes an armed band, &c. There was always in antiquity some confusion between the worship of Cybele in Phrygia and that of the Mother in Crete, which was heightened by the fact that in each place the scene of the worship was on Mount Ida. Modern investigation seems to show that the Phrygian worship was actually derived from the Cretan.

79. for you would see monsters, &c. Lucretius returns to this idea of the impossibility of the formation of monsters with parts derived from different races of animals, and supports it with rather different arguments in V. 878 ff.

80. that the mind cannot project itself into these bodies. A reference to a rather obscure idea in the psychology of Epicurus. The mind being an aggregation of soul-atoms, its thoughts are caused when these atoms are stirred by images coming from things outside or from its own stores (IV. 722 ff.). But the mind has a power of spontaneously ‘projecting itself upon’ the images (ἐπιβολὴ τη̑ς διανοίας), which results in attention, observation, selection, &c., or sometimes, when it so combines more than one image in its grasp, in the creation of a new conception. Here Lucretius imagines his reader as doubting whether it was possible for the mind by such an act of ‘projection’ to grasp the idea, i. e. to ‘visualize’, colourless atoms. He replies by the analogy of the blind, suggesting that we must think of the atoms as something which could be touched but not seen. Compare lines 1047 and 1080 of this book.

81. may become a clear concept. Another technical notion of Epicurus. The mind had ready in itself general notions or concepts of classes of things, to which it could refer, when any new instance of the class occurred; thus, we know, e. g. that ‘this is a horse’, because we have the general idea of ‘horse’ to which to refer (for this reason Epicurus gave the concepts the rather curious name of προλήψεις, ‘anticipations’). These general concepts were formed, in the case of perceptible objects, by the storing up in the mind of a series of single impressions, which formed a sort of ‘composite photograph’. But in the case of imperceptible things, such as the atoms, he probably conceived of their being formed by a combination of existing concepts by a ‘projection of the mind’. So here, by combining the concept of an atom with that of touch without sight, we get the ‘clear concept’ of a colourless atom. Easier cases of the application of the idea of ‘concepts’ will be found in II. 124, IV. 476, V. 124, 182, 1047.

82. It must needs be, &c. This proof, that things which themselves have sensation, are yet created of atoms that have not, is of course of immense importance for the next Book, in which Lucretius is going to prove that the soul is mortal.

83. Next, those who think, &c., a difficult and very tersely expressed argument. If there are sensible atoms, they must be like in substance to such sensible things as we know, veins, sinews, &c. If so, they are soft, and therefore not mortal, which is the very reverse of what Lucretius’s imaginary opponents would wish to prove.

84. still doubtless they must either have, &c. Again the argument is put very briefly and obscurely. He appeals once more to our experience. We only know two kinds of sensation, (1) the sensation of a complete sentient being, as when ‘I feel well’ or ‘happy’, (2) the sensation of a part of such a being, as when ‘my tooth aches’. If then the atoms, which compose sentient beings, have themselves sensation, it must be of one of these two kinds. But firstly, parts only have sensation as parts of a sentient whole: my tooth only feels as a part of me, and would not feel if it were taken out. In this case the individual atoms, apart from the whole compound, would have no sensation. Secondly, they may be each of them complete sentient beings; but then (a) like other sentient beings they must be mortal (see note on 902), (b) they could not by coming together produce one sentient being, but only a jumble of independent sentient beings, unless (c) in uniting they lose their own sense and combine to form the new sense of the compound being; in this case why attribute sense to them as individuals?

85. But if by chance any one shall say, &c. A slightly different position to that just dealt with. It may be admitted that the atoms are not sentient when separate, but they become sentient in the compound. No, replies Lucretius; by their union they form a sentient body, but the individual atoms always remain insentient.

86. whereof the race of men has its peculiar increment, i. e. the sensible atoms, which, according to the theory Lucretius is opposing, man has in addition to the non-sensible atoms which compose his body. This argument is of course not to be taken quite seriously: Lucretius is fond of finishing a series of serious proofs with a reductio ad absurdum. Compare III. 367, 776, and especially I. 918.

87. what we see floating on the surface of things is the ‘secondary qualities’, and especially colour, as he has explained at great length: what we see at times coming to birth and … passing away is similarly sensation. This paragraph is a summing up of all he has said from line 730 onwards.

88. the unfettered projection of our mind: see note on line 740. This is clearly a case where the mind, by its own free effort, puts concepts together to form a new conclusion.

89. in the universe there is nothing single: for this argument see note on line 532.

90. For it was no golden rope, &c. A reference to the famous passage in Homer, Iliad, 8. 19, where Zeus challenges the other gods to attach a golden rope to him and pull him down from heaven to earth. The Stoics had apparently interpreted the passage allegorically as referring to the creation of life on earth.

91. which neither the winds shake, &c. Again an allusion to a famous passage in Homer, Od. VI. 42 ff., which has passed on into English in Tennyson’s Morte d’Arthur.

92. that the soul’s nature is of blood, or else of wind. The theory that the soul was made of blood was that of Empedocles, of wind that of Critias.

93. First I say that the mind … All through this book we must distinguish carefully, as Lucretius does, between the mind (animus), which is an aggregate of pure ‘soul-atoms’ situated in the breast, and is the seat of thought and volition, and the soul or vital principle (anima), which is made of similar atoms, but scattered throughout the body and mixed with the body atoms, and is the cause of sensation in the body. Sometimes, however, when he is making statements which apply to both, he uses one or other of the terms in an inclusive sense.

94. which the Greeks call a harmony. Lucretius is thinking particularly of Aristoxenus, a pupil of Aristotle, who was a great theoretical musician, and applied his musical theory to the explanation of the human soul.

95. some fourth nature. This idea of the mysterious fourth nature, which is infinitely subtle, and is the ultimate cause of sensation and thought, has often been claimed as a practical admission by Lucretius of something supra-material or spiritual in the mind. But of course he conceives it as purely corporeal, just like any of the other component elements.

96. with the motions of first-beginnings. See II. 127 and the note on that passage; the idea of the internal vibrations of the atoms there illustrated is what Lucretius has in his mind here.

97. This nature then of the soul, &c. This notion of the very intimate union of soul and body, so that while the body protects the soul, the soul in return lends the body sensation is not very clearly expressed, but is of course of great importance for the subsequent discussion; neither soul nor body can continue to exist without the presence and help of the other.

98. if our eyes are as doors, &c. Another example of the reductio ad absurdum as the conclusion of a serious argument.

99. Democritus of Abdera (about 430bc), was, with Leucippus, the earliest exponent of the atomic theory. He is always regarded with great respect by Lucretius, who carefully notes this point, on which Epicurus differed from him (compare V. 621). See Introduction, p. 12.

100. the minds and the light souls … This is, of course, the main purpose of the book, to prove that the soul is mortal, and that therefore there is no reason to fear its punishment after death. There follows a rather bewildering series of twenty-eight proofs, which are not well classified or arranged by Lucretius, but we can distinguish three main lines of argument: (1) proofs from the previously described structure of soul and body; (2) proofs from death, disease, and cure, showing the close parallelism between soul and body; (3) arguments from the absurdity of the conception of the soul existing alone apart from body.

101. Be it yours, &c.: a warning that in this section he means to speak comprehensively of the mind and the soul, and that what is said of the one is applicable to the other. See note on line 94.

102. by images of smoke and cloud. A reference to the theory of ‘images’, or ‘idols’, as the cause of vision and thought which is expounded in Book IV.

103. And since the mind is one part of man. The mind, whose peculiar sensation, thought, is aroused, just like all other sensations, by touch, is here treated as practically another organ of sense.

104. the heart has had a shock, or the heart has failed: these are meant to be phrases of quite common parlance, and to translate them we must, I think, use ‘the heart’, though Lucretius uses his ordinary words for ‘mind’ and ‘soul’. Seeing that he placed the mind in the breast, the change is not so far wrong.

105. Nor in any other way can we picture to ourselves, &c.: notice that the test of truth is the possibility of ‘visualization’, as it must be for the Epicurean, to whom it was the only mode of thought.

106. Moreover, if when our body, &c. The argument of this paragraph is not so clear as it might be; it is really a dilemma. If an already formed soul enters our body at the moment of birth, (a) if it keeps its independent existence, it could never become so closely linked and connected with our body, as we see it is; (b) (line 698) if it is dispersed among the limbs, it does not maintain its existence, it perishes, and the soul in the body is a different soul to that which existed before.

107. Again, why does fiery passion, &c. An interesting argument in support of heredity as against the notion of the transmigration of souls.

108. Or why does it desire, &c. In this and the next paragraph we notice again the reductio ad absurdum towards the conclusion; it has already obtruded itself in lines 725 ff.

109. Again, a tree cannot exist in the sky, &c. A new line of argument, that everything in nature has its fixed place, and that of the soul is in the body. Lucretius applies the same argument again in almost the same words in V. 128 ff.

110. Moreover, if ever things abide for everlasting, &c. Another general principle, that there are certain fixed conditions for immortality, none of which the soul fulfils. Again Lucretius repeats the argument in Book V. 351 ff. to prove that our world is not immortal.

111. Death, then, is naught to us, &c. From here to the end of the book follows a kind of triumph-song over the mortality of the soul. ‘We need not fear death, for after it there is no part of us surviving to feel anything.’ It is really the climax of the poem.

112. he does not, I trow, grant, &c.: perhaps a little obscure. Such a man professes to grant that his soul does not survive his death on the grounds which Lucretius has just been discussing. But he does not in practice admit either the one or the other, as he half-consciously assumes that some part of him will survive to feel what happens to his body.

113. and to grow stiff with cold: this is not an alternative mode of burial, but goes closely with what has just preceded. After embalming, the Romans often left the corpse lying on a rock slab in the vault, or on the bier on which it was brought.

114. as though heaped in a vessel full of holes. Lucretius is thinking of the legend of the Danaids, to which he specially refers in lines 1008 ff.

115. to none for freehold, to all on lease. Lucretius is here using two technical terms of Roman law: mancipium was a full legal process of acquiring a possession, which gave the owner the most complete title to it, usus, the mere right of possession by custom, or ‘usufruct’. It seems best to accept parallel expressions in English, rather than to introduce their exact equivalents, which would have a very prosy effect, into the text.

116. Ancus the good. Of course Ancus Martius, the legendary fourth king of Rome. Lucretius takes this line from the Annals of Ennius.

117. he himself, who once … Xerxes.

118. I traverse the distant haunts, &c. These verses are repeated with a few slight changes, from I. 921 ff.

119. idols: it seems best to translate Lucretius’s word simulacra in this way, as it is itself a translation of Epicurus’s word εἴδωλον. The famous theory of vision is clearly explained here by Lucretius himself.

120. above all, since on the surface of things, &c.: a passage with more meaning than is at first apparent. When in the compound body all the atoms are moving at great speed in their tiny trajectories (see note on II. 527), it is obvious that those in the inner part are well hemmed in. But those on the surface have none outside to beat them back, and so are much more liable to break away from the object; it is these then that form the films, which produce vision.

121. first, because it is a tiny cause, &c. This is a very esoteric piece of Epicurean physics. We saw (see note on II. 127) that the speed of the unimpeded atom was much greater than that of any compound of atoms, however small, as the latter is checked by internal vibration. For the same reason the impact of the unimpeded atom is greatest, and it can therefore impart greater speed to any object which it hits. The films are sent on their way by the blows of other single atoms inside the compound, and the ‘tiny cause’ is therefore able to impart great speed to them.

122. Moreover, when particles of things, &c. Another rather abstruse piece of theory. Particles coming from deep within things are obstructed and jostled by the atoms, through which they have to make their way, and therefore have their speed diminished. But those which start from the surface, start, so to speak, without this initial handicap, and therefore attain a much greater rate of motion.

123. But because we can see them only … A very confused statement. Lucretius seems to be combining two points that he wished to state: (1) that these images are constantly hitting us in all parts of our body, but we can only see them with our eyes; (2) as the images are constantly streaming off bodies on all sides, wherever we turn our eyes, we see them.

124. For when it is given off, &c. Not a very satisfactory account. For (a) how can our eyes measure the length of this ‘draught’ from objects which passes through them; (b) even if they could, how can they know at what moment the ‘draught’ from any particular object, which they are going to see, begins?

125. Herein by no means must we deem, &c. An important point. We do not see the individual ‘idols’ of things, but their constant succession gives us a ‘cinematographic’ impression of the whole object.

126. flank-curved mirrors: probably a special name for concave horizontal mirrors.

127. or else because the image, &c.: a very ingenious but not very clear explanation. The idea is that with a flat mirror the whole surface of the image meets the mirror at once and is returned as it is, but with the curved mirror one corner of the image would touch it before the rest, and the result would be that the image would be given a twist and turned round so that it reached us again ‘right-handed’.

128. inasmuch as nature, &c.: as we say in modern scientific language, the angle of reflection is equal to the angle of incidence. These two lines ought possibly to be placed, as Giussani suggests, after line 307, where they would be more immediately in place. Here they give a general principle, which is the real cause of all the last four phenomena.

129. And when we see from afar off, &c. The problem of the square tower, which seems round at a distance, was one of the traditional difficulties of the Epicurean school. This explanation, however, tends to destroy our trust in the ‘idols’ as true evidence of things, and it is doubtful whether it was Epicurus’s own.

130. The ship, in which we journey, &c. There follows an interesting list of ‘optical illusions’, in all of which Lucretius holds that the mistake lies not in the sense-perception, but in the inferences made by the mind.

131. Again, if any one thinks, &c. This protest against scepticism and vindication of the veracity of the senses is the keystone of the whole Epicurean philosophy: every other part of it really depends on this.

132. the concept of the true and the false. The concept, as we have seen (see note on II. 744), must be produced by a series of individual experiences. If a man has never perceived anything true with the senses, how can he have the concept of truth?

133. Will reason, sprung from false sensation, &c. Reason is based on the senses, for its function is to distinguish and correlate the impressions given by the senses. If then the senses are false, much more must reason be: it cannot act as a criterion of the truth of sense-perceptions. The same idea is found in a famous passage of Democritus, quoted in the Introduction, p. 13.

134. all that goes along with colour is form in its various aspects of surface-outline, bulk, size, &c.

135. First of all, every kind of sound, &c. Sound is in Lucretius’s idea a corporeal emission, much like the ‘idols’ of vision, which strikes upon the ear.

136. Nor do the tongue and palate, &c. The case of taste is easy, because it can be accounted for directly by touch, and it is not necessary to assume the intervention of emissions.

137. Come now, I will tell, &c. In the case of smell Lucretius has again to assume the effluence or emission to act as a link between the nose and the object.

138. Firstly, because coming from deep within, &c. Compare the argument in lines 199 ff., and the note there.

139. Nay, indeed, ravening lions, &c. This curious fact is vouched for by Pliny and Plutarch.

140. Come now, let me tell you, &c. The mind being an aggregation of corporeal atoms, just like eye or ear, thought must be produced just like sight or hearing, by the stirring of the atoms of the mind by ‘idols’.

141. And in these matters, &c. Another obscurely expressed passage. The main idea is simple, if we bear in mind always the Lucretian conception of thought as ‘visualization’. The mind can think of whatever it will, because there are at all times present to it ‘idols’ of every sort, and it can turn its attention to any one of these it likes by a ‘projection’ (see note on II. 740).

142. Herein you must eagerly, &c. An argument against the teleological view of nature, which Lucretius of course dislikes because it might seem to support the theological idea that the gods made the world with a purpose. The eye, says Lucretius, was not made in order that we might see, but because it has been created we do see.

143. For verily I have shown, &c. Compare especially II. 1128 ff.

144. Then comes the will, &c.: this passage should be read in connexion with the theory of free-will, and its origin in the slight swerving of the atoms in II. 216 ff.

145. that the body, like a ship, is borne on by sails and wind. This is almost certainly the sense of this corrupt line, but the parallel does not work out very well. The sails should correspond to the act of will in the body, the wind to the external force, the air entering the pores. But the sails are of no use without the wind. It is possible, as has been suggested, that the ‘two things’ are the entering air and the parts of the body which it reaches. This would make the parallel more satisfactory, but does not seem likely to be what Lucretius meant, as the distinction would not be important enough.

146. First of all sleep comes to pass. Notice again the purely material explanation. Sleep is the absence of sensation, which is due to the soul. It must be then that the soul-atoms in sleep are either scattered about in the body, or driven out of it, or retreat far within below the surface. Even more strictly physical is the account in the next paragraph of how this comes to be.

147. it is best to flee those images, &c. The attack on love was part of the traditional philosophy of Epicurus, who thought it destructive to a man’s peace of mind to be too dependent on others, but we cannot help remembering all through this passage the story that Lucretius himself was maddened by a love-philtre, and ultimately driven to commit suicide.

148. of Hercules: Lucretius deals at such special length with Hercules because he was adopted as their particular hero by the Stoics.

149. the giants, who attempted to assail heaven by piling Pelion on Ossa, and were punished by imprisonment beneath the earth, Enceladus being shut beneath Etna.

150. all which I will hereafter prove to you: but he never does. It has been thought, with much probability, that Lucretius’s intention was to close the whole poem, after the description of the plague of Athens, with a discussion and picture of the nature and life of the gods, clinching the whole argument of the poem with the proof that they could take no part in the government of the world. He does indeed return to the question of the origin of religion in this book (lines 1161 ff.), but that passage cannot be what he refers to here.

151. the concept of man. This is a very good instance of the technical idea of the ‘anticipation’ (see note on II. 744). If the gods had not in their minds a ‘concept’ of man, resulting from previous sense-perceptions, how could they have set about to make a man? One is tempted to reply ‘after their own image’.

152. But even if I knew not, &c. Lucretius’s rather crude contribution to the problem of the existence of evil.

153. First of all, &c.: the poet now returns, after the long digression about the gods and the theory of the divine creation of the world, to the point which he left at line 110, that the world had a birth and will be destroyed.

154. Likewise that bounteous source, &c. A rather subtle notion: that what appears to us as a continuous stream of light from the sun, or even from torches, &c., on earth, is really a constant succession of small particles of light, the foremost ever perishing, and their place being taken by fresh particles from behind.

155. as some tell: of course the Stoics as usual. This passage is interesting, as it is an adaptation by Lucretius of verses in which the tragic poet Pacuvius had expressed the Stoic doctrine.

156. Moreover, if ever things abide, &c. Compare III. 806 ff. and the note on that passage.

157. Moisture likewise, &c. The story of the flood of Deucalion and Pyrrha was of course familiar in antiquity. Compare e. g. Horace, Odes i. 2. 5 ff.

158. From this mass, &c. This idea of an original chaos, out of which a world was formed by the union of the like and the separation of the unlike, was, in its main outlines, traditional among the Greek physical philosophers, but Epicurus explained how it might be brought about without the gratuitous assumption of an unaccountable ‘whirl’ or an arbitrary ‘necessity’, such as previous thinkers had assumed.

159. if the great globe of the sky turns round, &c. The ideas of Lucretius’s astronomy are often curious and complicated, but we must always bear in mind that he conceives the world as a sphere, in the centre of the interior of which is suspended the earth; moon, sun, and stars move round it in orbits at ever-increasing distance, and above them, forming the ‘walls of the world’, comes the ether. The axis of the world he conceived to be inclined. In this passage he first considers the theory that the world as a whole moves round; we must then conceive it as held firm at each end of its axis by the pressure of air at each of the poles (P), and then caused to rotate by a current either flowing above (a, a) in the direction in which the heavenly bodies are seen to move, or below (b, b) in the opposite direction, as a water-mill is moved by the stream flowing beneath it. He then considers other ideas which may be advanced on the supposition that the world does not move round as a whole. He puts them forward as all worthy of consideration on Epicurus’s principle, that where our senses do not give us direct information, we ought to consider as possible all explanations which do not conflict with the evidence of the senses.

lf1496_figure_001.jpg Fig. 1.

535. it is natural that its mass should, &c. A very curious idea: that the earth on the underside gradually ‘thins out’ and so forms a light ‘second nature’ beneath it, which makes a link to connect it with the air beneath it, and so acts as a kind of ‘spring-mattress’, by which it is continually supported, and does not press heavily on the air.

536. Nor can the sun’s blazing wheel, &c. This paragraph illustrates a principle of Epicurus complementary to that found in 510 ff.: that, where the senses do give us evidence, we must trust it absolutely. Our sight tells us that sun and moon are of a certain size: they must, then, be of that size. He supports the theory with the curious statements that even on earth fires and lights do not appear to diminish in bulk, so long as they send out light and heat, nor so long as their outline is clear and not blurred.

537. This, too, is not wonderful, &c. In this paragraph again, as in many others that follow, we see the principle that all explanations, not contradicted by the senses, are to be considered as possible.

538. For it may be that from this spot, &c.: the idea is that the sun is an opening, or breach in the ‘walls of the world’, through which myriads of particles of light from outside the world stream into it.

539. Nor is there any single account of the sun, &c. An obscure section, because Lucretius is guilty of confusion. The apparent path of the sun in the heavens has two notable features: (1) he appears to make a complete circuit of the heavens in the year, from west to east, just as the moon does in a month, and the planets in longer periods than the sun; (2) this circuit is not in the same plane as the equator: wherefore it seems that the sun goes up and down as well as round. Of the two explanations given by Lucretius, the first (621-36) would explain the former phenomenon, the second (637-45) the latter, but Lucretius has unfortunately represented them not as concurrent explanations of a complex phenomenon, but as alternative explanations of the whole.

lf1496_figure_002.jpg Fig. 2.

(1) Democritus’s theory of the relative orbits of sun, moon, and planets may be explained by the accompanying diagram (Fig. 2). Suppose that in a given time the stars have actually moved on the outer rim of the world from a to α: the planets moving more slowly, as they are nearer the earth and thus less influenced by the ‘whirl’ of the heavens, will in the same time have moved from b to b1, the sun from c to c1, and the moon, slower still, from d to d1. But with reference to the stars, which seem fixed, the planets seem to have moved from β to b1, the sun from γ to c1, and the moon from δ to d1.

(2) But this orbit being set in a different plane to that of the equator, the effect is of the sun passing down towards the south in the autumn until in winter he reaches the tropic, or turning-point of Capricorn, and northwards in the spring until in summer he reaches the tropic of Cancer. This, it is suggested (637-49), was brought about by winds blowing ‘athwart his course’.

lf1496_figure_003.jpg Fig. 3.

643. those stars which roll through … i. e. the planets.

644. either when after his long journey, &c.: this theory, that the sun was extinguished each night, and a new sun lit in the morning, was that of Heraclitus: the other is the normal idea of ancient astronomy.

645. Likewise at a fixed time, &c. The two following theories of the dawn correspond exactly to the two immediately preceding theories of the sun’s light; if he completes a circle under the earth, dawn is the advance light of his return; if a new sun is created each day, dawn is caused by the light gathering to form the sun.

Matuta was an ancient Roman deity of the dawn.

682. either because the same sun, &c. Another difficult section, though its general meaning is comparatively clear. The sun performs apparently both an annual orbit round the heavens, with which Lucretius has already dealt (614-49), and also a daily revolution. At most times of the year he divides the circle of the daily revolution unequally: in the winter he is for the greater part below the horizon, so that night is longer Fig. 4 (1); in the summer he is for the greater part above the horizon, so that day is longer (3); but at the equinoxes he divides his circle exactly into semi-circles, so that day and night are equal (2). This occurs twice in the year, at the equinoxes or ‘nodes’, the points at which the sun’s orbit cuts the equator (Fig. 5). The exact interpretation of lines 689-93 has been very much disputed, especially with regard to the precise meaning of the ‘turning-points’: are they a point in the annual orbit or in the daily revolution? I take the whole passage to depend on what Lucretius has already said about the annual orbit in lines 614-49: ‘the blast of the north wind and of the south’ refers to the theory that the sun was blown out of his natural course to the tropics: the ‘turning-points’ are, just as they were in line 617, the tropics. The passage means then, that mid-way in the sun’s course from north to south and south to north the sun holds his ‘turning-points’ at equal distances apart; i. e. he is on the equator. The effect of this, Lucretius implies but does not state, is that day is then exactly equal to night, for when the sun is on the equator he rises due east and sets due west—in other words, his daily revolution is exactly along the line of the equator, and is therefore performed, as may be seen from the figure, exactly half above and half below the horizon.

lf1496_figure_004.jpg Fig. 4.

lf1496_figure_005.jpg Fig. 5. T=the Earth; PP=the Poles; NESW=the Horizon; EQWR=the Equator; ΩCΓL=the Eliptic; ΩΓ=the Equinoxes or Nodes.

(A fuller description and explanation of Lucretius’s idea of the ‘heavenly globe’ may be found in the introduction to Mr. J. D. Duff’s edition of Book v, to which I am much indebted.)

696. Or else, because, &c.: this second explanation still rests on the assumption of ‘the same sun’ performing a daily journey under the earth, whereas the third (line 701) depends on the Heraclitean notion of a new sun being kindled every day (compare lines 651 ff. and 660 ff.).

697. The moon may shine, &c. Similarly in this paragraph the first three explanations regard the moon as passing below the earth and re-appearing, the fourth (line 731 ff.) assumes the creation of a new moon every day. Lines 729-730 are a very emphatic expression of the principle that we must accept all explanations equally, if they do not contradict phenomena.

698. the Babylonian teaching of the Chaldaeans, especially the theory of Berosus.

699. Spring goes on her way and Venus, &c. This description is probably based on some pantomimic representation of the Seasons, or on a picture. Modern readers naturally think of Botticelli’s ‘Primavera’, and indeed it is not at all unlikely that that picture was actually founded on this passage, as his ‘Mars and Venus’ almost certainly was on a passage of Politian in the Giostra, which was based on Lucretius’s description in Book I. 31-40.

700. Likewise also the eclipses of the sun, &c. None of these explanations present any difficulty with the exception of the first theory of the eclipse of the moon (762-4). This is, of course, the correct explanation: the earth, obstructing the rays of the sun, forms a shadow in the shape of a cone, and when the moon passes into it, it is eclipsed (Fig. 6). But it is, of course, quite inconsistent with the Epicurean theory that the sun and moon are the size we see them, i. e. both very greatly smaller than the earth, for in that case the shadow thrown will not take the form of a cone at all, and the eclipses of the moon would be of much more frequent occurrence and longer duration than they are (Fig. 7). This is the most important of several indications that Lucretius did not really understand his astronomy, and took much of it from the ordinary astronomical hand-books, without considering carefully how far it could be reconciled with Epicurean principles.

lf1496_figure_006.jpg Fig. 6.

lf1496_figure_007.jpg Fig. 7.

808. there grew up wombs: a curiously naïve device, by which Lucretius tries to account for the transition from vegetable to animal life. He seems to be a little conscious of its improbability, and is careful just afterwards (813) to supply an analogy for this apparently gratuitous act of kindness on the part of the earth.

809. And many monsters too earth, &c. In this idea of the early experiments of nature we get a glimmering of the modern notions of Evolution and Natural Selection, which become more prominent in the next paragraph. It is one of Lucretius’s most remarkable anticipations of modern scientific belief.

810. But neither were there Centaurs, &c. The impossibility of the formation of monsters of this sort, combined of parts belonging to different races of animals, has been dealt with already in II. 700 ff.

811. But the race of man, &c. Lucretius’s study of primitive man, again, has always been admired for its insight, and is all the more remarkable when one remembers the strong prevalence in antiquity of the notion of a Golden Age.

812. not to burt or be barmed. Here we have the germs of the theory of the Social Compact as the origin of Society.

813. But the diverse sounds of the tongue, &c. There was always a controversy in antiquity as to whether language was made by convention (θέσει) or grew up naturally (ϕύσει). Lucretius, consistently with the attitude taken up all through this book, decides for the latter view.

814. the concept of their use. See note on II. 744.

815. For indeed already the races of mortals, &c. It is a matter of great difficulty to decide exactly how Epicurus and Lucretius conceived the immortal nature of the gods, and the evidence is very insufficient. But it is certain that they supposed them to dwell in the ‘interspaces between the worlds’ (intermundia), and to become known to men by a constant succession of ‘idols’, which streamed off their bodies, preserving the ‘form unchanged’, and, being too subtle to be perceived by the senses, passed through the pores of the body into the mind, and there stirred the soul-atoms.

816. with veiled head turning towards a stone, &c. Lucretius is here carefully recalling the ceremonial of Roman worship. The Roman always veiled his head (as opposed to the Greek), approached with the image of the god on his right hand, and in this position made his prayer. He then turned towards the image and prostrated himself on the ground.

817. the glorious rods and relentless axes, the insignia of the Roman magistrates.

818. the form of the bronze sickle, &c. Lucretius is probably thinking of its use for purposes of magic.

819. the Lucanian kine, i. e. elephants, which were said to have been so called because they were first seen by the Romans in Lucania in the army of Pyrrhus.

820. And you could more readily maintain, &c. For this curious argument that if this practice did not obtain on our earth, it probably did somewhere in the universe, compare what Lucretius says in 526 ff. about the motions of the stars.

821. in part because he saw that it was leaking, &c.: for this description of the human mind compare the explanation of the legend of the Danaids in III. 1003 ff.

822. be it by the chance or the force of nature. One of the few places where Lucretius in so many words implies that nature does act by chance, as well as by law. That there is the element of chance is probably due to the original swerving of the atoms; see Introduction, p. 18.

823. not that the high majesty of the gods, &c. A particularly interesting passage for the Epicurean conception of the relation of man and the gods. The superstitious beliefs of the old religion are an offence against the majesty of the gods, living their placid life untroubled by the world. Yet they will not lead to direct punishment at the hands of the gods, for that is impossible. But they will prevent those who hold them from approaching the gods with the proper tranquillity of spirit, and so deriving the greatest benefit from their worship. The passage shows clearly that the gods were to men a perfect example of the ideal life, and that their worship should be one of contemplation; it also explains how, when, as we are told, Epicurus himself and his immediate followers scrupulously attended the ceremonies of religious worship, they may have done so without inconsistency.

824. because things always move more slowly, &c.: another notable piece of Epicurean observation, that light travels more quickly than sound.

825. Once again, because it comes with long-lasting impulse, &c. This conception of the thunderbolt gathering speed as it goes, and the accompanying explanation, are based on the fundamental Epicurean notions of the movement of bodies (see note on II. 127.) In any compound body, even of so rare a texture as the thunderbolt, there is, of course, internal vibration, and though the whole body is moving in one direction the atoms which compose it will be moving in all directions and colliding with one another, and so retarding it. But there is always a tendency that the sideways and upward movement of the atoms resulting from blows should in time yield to their own natural tendency to fall owing to weight. In the case of a falling body this means that more and more atoms are always coming to move in the direction of the whole, and that therefore the speed of the whole body tends continually to increase. Lucretius has not expressed this very clearly, but considering the passage in the light of the general theory of motion, this must be its meaning.

826. the narrow channel is not to be thought of as something which separates lands, but rather as something which connects seas and mixes their waters (e. g. the Straits of the Bosphorus). So here, spring and autumn join the cold of winter with the warmth of summer.

827. the Tyrrhenian prophecies: it was generally supposed that the Romans obtained their system of auguries and omens from the Etruscans.

828. But if Jupiter, &c. Lucretius, in concluding this long section on the phenomena of thunder and lightning, comes back to his main purpose of attacking the traditional religion and its superstitious beliefs.

829. presters, i. e. fiery whirlwinds (πίμπρημι).

830. clear fact demands, &c. It is not obvious at first sight why this should be so. It may be that here we have another, and rather arbitrary, application of the curious principle of equilibrium (ἰσονομία). Compare II. 532 and the note there. But more probably he is thinking of his description in V. 492 ff. of the formation of the irregular surface of the upper earth, and argues on grounds of general probability that the same sort of process had taken place on the lower side.

831. the holy fire was the name given in antiquity to erysipelas; compare Virgil, Georg. iii. 566.

832. For air becomes wind, when, &c. This is not such a puerile comment as it looks at first sight, for to Lucretius ‘air’ and ‘wind’ were two distinct, though kindred, substances. (Compare the account of the composition of the soul, III. 231 ff.) The air, then, by being ‘set in motion’, would lose some of its own characteristic atoms, and acquire others, which would convert it into wind.

833. the name Avernian. Avernus in its Greek form Ἄορνος means ‘Birdless’.

834. because of their vigil. The story (told by Ovid, Metam. II. 542-565) was that the daughters of Cecrops, against the orders of Pallas, opened the chest containing the infant Erichthonius. The crow, who was on the watch, flew off and told Pallas, but she, in furious anger at what had been done, banished him for ever from the Acropolis.

835. Scaptensula: the Latin name for the famous mines of Σκαπτὴ Ὕλη in Thrace.

836. the shrine of Ammon: of course of Jupiter Ammon in the Libyan desert. As Giussani remarks, the possession of a thermometer in antiquity would have made considerable difference to these observations.

837. at Aradus: an island off the coast of Phoenicia, whose fresh-water spring was famous. The point of the comparison is of course simply that the seeds of fire well up through the water, just as the fresh water does through the salt at Aradus.

838. in the beginning of my poem too: he is thinking primarily, no doubt, of I. 329, &c., where he showed that ‘there is void in things’, but also of II. 95 ff., where he explained in what manner this occurred.

839. Again, where the breastplate of the sky, &c. This passage has been much discussed and very variously corrected and explained, but Giussani’s view seems much the most probable. As a crowning instance of the porosity of things, the poet takes the world itself: though it is surrounded with a breastplate (compare ‘the walls of the world’, I. 73, &c.), yet even through this there penetrate, as he has described in lines 483 ff., storms, tempest, and pestilence.

840. First of all it must needs be, &c. Lucretius’s exposition in this paragraph is not quite so orderly or lucid as usual, but it all follows quite directly from his main principles. Ordinarily things are surrounded on all sides by countless moving atoms, which batter against them and are in part the cause of their holding together. The effluence streaming off from the magnet knocks away these particles and creates a void between itself and the iron ring. The atoms on that side of the ring are therefore impelled by the internal air and vibration, and the external air and battering particles on the other sides, to move towards that part, where there is now no opposition. This they proceed to do, but because the atoms of iron are so closely interlaced, they cannot disentangle themselves, but of necessity drag the whole ring along with them towards the magnet.

841. where the axis of the world slants crippled. The ancients conceived that the axis of the earth (and consequently also of the world) was on a slant, rising towards Scythia and sinking towards Egypt. Just the same idea is found in Virgil, Georgic I. 240. The idea is characteristic of the atomic school, and is found in Leucippus (Aet. 12. 1, Diels, Leucippus, 27).

842. Such a cause of plague, &c. Lucretius here describes the famous plague of Athens in 430 bc, and very closely follows the account given by Thucydides ii. 47-54.