Cicero’s death occurred in 43 b.c., when he was almost sixty-four years old, and his philosophical works belong to the two years immediately preceding. The circumstances under which they were undertaken he indicates himself in his preface to the present work (i., 4). He was, he says, urged to them as a means of relief from the irksome political inactivity to which he was reduced by the supremacy in the state of Julius Cæsar, and he also hoped to find in them a distraction from the grief caused him by the death of his daughter Tullia. He felt, too, that for the sake of the national credit it was right that the philosophy of Greece should be brought before his countrymen in their own tongue, and in the case of the special branch of philosophy discussed in the De Natura he had another and more pressing motive. For it was necessary there to consider those theological questions the answers to which determined the character and even the possibility of religion, and therefore, in his opinion, of morality as well. If the very existence of divine beings were denied, as some philosophers had denied it, clearly religion, and with it morality, at once disappeared (i., 2). Nor was the case much improved if the view of the Epicureans were adopted. It was true that they had released mankind from a superstitious fear of the gods, but only by holding out deities who were absolutely regardless of the world and its affairs, who led a shadowy and undefined existence, and were for practical purposes non-existent. Religious worship as directed to such beings could only be an empty form, and it was impossible for morality to flourish upon a basis of insincerity. The Stoics gave a noble account of the divine government of the universe and care for man, but their excessive dogmatism exposed them to the criticisms of the Academy.
It is of this latter school that Cicero in i., 3 professes himself an adherent. Its original founder was Plato, but in its later development it had come to neglect the positive side of his teaching, and to base itself solely upon the negative dialectic which always played so important a part in his system. By means of this weapon Carneades (213-129 b.c.), the most important representative of the Middle or Sceptical Academy, set himself to controvert the Stoic doctrine of certain knowledge, endeavouring to show that real knowledge was impossible, and a greater or less degree of probability all that could be attained. He was also a formidable critic of the argument from design employed by the Stoics, and of their conception of God as a living, rational being. This purely negative attitude was modified by the later Academics of Cicero’s own time, who formed what is called the New Academy. Philo (ob. about 80 b.c.) made a partial return to Stoicism, attempting a compromise on the lines indicated in i., 5, ad fin., between mere probability and absolute certainty. A much stronger tendency towards eclecticism was shown by his disciple Antiochus (ob. 68 b.c.), who thought that truth might be found in that upon which all philosophers were agreed, and tried to prove, inevitably without much success, that the Academic, Stoic and Peripatetic systems were in substantial harmony (i., 7). Cicero himself should really be ranked as an eclectic. At the close of this dialogue he declares that he finds a greater appearance of “probability” in the arguments of the Stoic disputant, and there is no doubt that though ready to adopt the standpoint of the Academics where abstract questions of metaphysics were concerned, and though in sympathy with them as an orator because of the effective use to which their method could be put in oratory, he was of too serious a temper to apply their scepticism to beliefs which affected practical life and conduct. He was a Stoic in regarding the consensus gentium as valid testimony to the existence of a supreme being, and as a statesman and patriot was convinced that it was the duty of a good citizen to accept and maintain the national religion.
As a student of philosophy Cicero held a foremost place among his contemporaries. He remained in touch with it during the whole of a busy life, not only, as his letters show, as a reader, but also as a writer of translations and adaptations, of which he left a large number behind. In his youth he had known as teachers the chief representatives of three schools. In 88 b.c., when eighteen years old, he had studied at Rome under Phædrus the Epicurean and Philo the Academic; in 79 b.c., at Athens, under the Epicureans Phædrus and Zeno and the Academic Antiochus, and in the following year under Posidonius the Stoic in Rhodes. Diodotus the Stoic was for some years an inmate of his house. The Stoics most frequently quoted in this dialogue are Zeno, the founder of the school (circ. 342-270 b.c.), Cleanthes (331-251 b.c.) and Chrysippus (280-206 b.c.). Panætius (180-111 b.c.), who is mentioned in ii., 46, was the chief exponent of Stoicism amongst the Romans. He lived in Rome for several years as the friend of Scipio Æmilianus, and a member of the “Scipionic circle” which did so much to foster the first growth of culture in Rome. Posidonius, who died about 50 b.c., was a disciple of his. The Peripatetic school is only referred to once in the De Natura (i., 7). It was identical with the Lyceum, the school founded by Aristotle, and in Cicero’s time was mainly occupied in the task of re-editing and commenting on Aristotle. It held a high position, but was comparatively colourless, and had nothing like the same hold on men’s minds as the three other systems. Cicero himself speaks of it elsewhere with respect, but without enthusiasm.
The dialogue is supposed to take place in Rome at the house of Caius Aurelius Cotta. Cotta was born in 124 b.c., and was a member of that party in the senate which, under the leadership of Drusus, urged the extension of the Roman citizenship to the Italian allies. The murder of Drusus in 91 b.c. was followed by the insurrection of the allies, and Cotta with many others was banished as having been guilty of high treason in encouraging the revolt; he did not return to Rome until order was restored by Sulla in 82 b.c. In this dialogue he appears as pontiff, but not as consul. We know that he was made pontiff soon after 82 b.c., and consul in 75 b.c., and as Cicero, who is present at the dialogue as a listener, did not return from Athens till 77 b.c., its date is limited to some time between the years 77 and 75 b.c., when Cicero would be about thirty years of age, and Cotta about forty-eight. Cotta represents the Academics. He was a distinguished orator, and appears as one of the speakers in the De Oratore, where he is represented as saying (De Orat., iii., 145) that he will not rest till he has mastered the Academic method as a part of his training in oratory. It is interesting to note that while an Academic in opinion, he is as pontiff the champion of orthodoxy (i., 22; iii., 2). The Epicureans are represented by Caius Velleius, and the Stoics by Quintus Lucilius Balbus, of both of whom scarcely anything is known beyond what is gathered from the dialogue itself. Cicero had also introduced Balbus as a speaker in the lost dialogue Hortensius, which was an appeal for the study of philosophy.
The present work is dedicated to Marcus Junius Brutus, afterwards the murderer of Cæsar. He was a man of considerable philosophical attainments, an adherent of the Stoicised Academy of Antiochus, and himself an author. Cicero, who was twenty-one years his senior, must have thought highly of him, as he dedicated to him four of his other treatises, and named after him the dialogue De Claris Oratoribus, in which he takes part. The De Natura itself was very possibly not published until after Cicero’s death, and was certainly not revised by him. This is shown, apart from various obscurities and inconsistencies which occur in it, by the allusions made to the time which the dialogue occupies. It is really supposed to take up one day, but in ii., 29 it is represented as having reached its second day, and in iii., 7 its third.
In this, as in his other philosophical works, which he himself calls ἀπόγραϕα, or “adaptations,” Cicero borrowed largely from Greek sources. There are many points of resemblance between the Epicurean section of book i. and a religious treatise of Philodemus discovered in an imperfect state amongst the Herculanean MSS. Philodemus was a leading Epicurean, a disciple of Zeno, and a contemporary of Cicero, who mentions him with praise, and it is generally supposed that he borrowed directly from him. But Mayor points out that the divergences are even more striking, and thinks that they both copied from an earlier authority. It is a strong argument in support of this that in both cases the list of philosophers criticised stops at the middle of the second century b.c. The rest of book i., which consists of Cotta’s criticism of the Epicurean position, is derived in great part from the Stoic Posidonius, who is also followed in the second book, which contains the Stoic exposition. The Academic criticism of the Stoics, which comes in book iii., is taken from the Academic Clitomachus (circ. 180-110 b.c.), the disciple and exponent of Carneades, who himself left no written remains.
The speech of Velleius, which opens the discussion, begins with a criticism of the Platonic and Stoic theologies (i., 8-10). The style is rather blustering, in accordance with the Epicurean reputation for arrogance and self-sufficiency, and the questions asked may in more than one case be answered out of the very writer criticised. The best points made are those which deal with the difficulty of supposing the creation of the universe to have taken place at a particular period of time, and with the question of what were the motives of the Creator in undertaking the work. These points, unfortunately, are not directly met by subsequent speakers, a fault observable through the entire work, which suffers from a want of cohesion attributable to the hasty use by Cicero of authorities who themselves wrote independently of one another. The critical section is succeeded by the historical (i., 10-15), which consists of a summary of the views of a large number of philosophers, together with criticisms upon them. It is an undeniable blot upon the book, being throughout full of inaccuracies and mis-statements, of which it is probable that Cicero himself was to a great extent unconscious; if they were intended to illustrate the ignorance, upon which the Epicureans prided themselves, of any writings besides their own, one would have expected a hint to that effect, if not a correction of blunders. Cotta, moreover, is made to compliment Velleius afterwards upon the accuracy of his sketch. The principle upon which the criticism proceeds is that the Epicurean idea of God as a perfectly happy, eternal being, possessed of reason, and in human form, is the only tenable one, and the mere statement of different opinions is regarded as a sufficient proof of their worthlessness. There is much more positive value in the Epicurean exposition which follows (i., 16-20). The Academic criticism, which takes up the rest of the book, is flippant, amusing, often obviously unjust, but often acute and to the point. The objections to endowing God with a human form (i., 27-37) are well put, and there is real humour in the bantering to which Epicurus is subjected in i., 26.
The second book will always rank as one of the chief attempts made in ancient literature to prove the divine existence, the providential ordering of the universe, and the providential care for man. In discussing the second of these points a number of details are introduced in connection with astronomy, animal and vegetable life, and the physiology of man, which make the book important in another way as a contribution to our knowledge of ancient science. The astronomical section is extended by selections from Cicero’s Aratea, a translation which he made in early youth of the Phænomena of the Stoic poet Aratus. The verses are spirited, and have received the honour of several imitations by Lucretius, but they might well have been spared in exchange for a fuller treatment of the dealings of Providence with the individual, such as would in all probability be contained in the original from which Cicero was borrowing. As it is, the problem of how to account for the presence of misery and disaster in a world providentially governed is only hurriedly touched upon at the end of the book.
Though we may be sure that Cicero would have been in sympathy with the main outlines of the Stoic exposition, we know from his other writings that he would not have agreed in the identification of heat with intelligence (ii., 10), or in ascribing life and thought to the universe and the heavenly bodies (ii., 13, 15), or in the attempts made to explain the gods of the popular religion (ii., 23-27). In this last connection chapters 25-27 are noticeable for their etymological explanations of the names of divinities.
Of the last book a large portion, probably more than one third, has been lost. This includes the whole of the section on the providential government of the universe, and part of that on the care of the gods for men. The Academic criticism here has the same general faults and merits as that in book i., but is more serious in tone. There is force in the objections brought in chapters 4-6 against the arguments in support of the divine existence which the Stoics derived from the general belief of mankind, the recorded appearances of gods, and the practice of divination. Chapter 15 is interesting as an attempt to show that virtue, as it is understood by man, is incompatible with the divine nature. The ten chapters following are devoted to a tedious and disproportionably lengthy discussion of the Stoic mythology. The arguments underlying it have a logical and philosophical value, but instances are multiplied to an inordinate extent. Chapters 21-23 contain a descriptive list of deities bearing the same name, and are designed to show that though the Stoics may wish to retain, by means of their allegorical explanations, the gods believed in by the people, it is impossible to decide out of so many claimants to a title which is the true god. The mythology in these three chapters is throughout eccentric; many of the particulars given are opposed to the ordinary account, and many are found nowhere else. At the same time it is singularly incomplete, deities so well known as Juno, Ceres, Neptune, Mars, Pluto, Hecate, and Proserpina being omitted. The original author of this part of the mythological section was probably one of the learned antiquaries of Alexandria, of whose labour Carneades or Clitomachus availed themselves for polemical purposes.
The remainder of the book is devoted to a vigorous attack upon the Stoic doctrine of the providential care for man. Two statements in it may be noted as inconsistent with statements already made in book ii. In iii., 36 it is said that all men are agreed in considering virtue to come from oneself and not from God, but the opposite was explicitly stated in ii., 31, and in iii., 39 the Stoics are quoted as saying that the divine care does not extend to individuals, which again is contradicted by ii., 66. In both cases it is probable that the earlier Stoics did hold the beliefs in question, and the discrepancy illustrates the difficulty under which Cicero lay in answering a later Stoic treatise out of an earlier Academic one. We find that when speaking in his own person he inclines rather to the Stoic view of the misfortunes of the good and prosperity of the bad, and in ascribing a divine origin to virtue and conscience he is again at variance with the Academics. The impression sometimes produced by this third book may be seen from the statement of Arnobius (circ. 300 a.d.) that many of the pagans themselves were scandalised by Cicero’s religious writings, and thought that they should be destroyed. On the other hand, the Stoic exposition, and passages of a similar tendency in other works, led to Christians recognising in Cicero an element of positive Christianity. Besides Arnobius, the Christian writers Tertullian, Minucius Felix, Lactantius, and Augustine were acquainted with the De Natura, and their arguments against polytheism are largely borrowed from it. Nor can the dialogue be regarded as without considerable claims upon our own attention. It possesses a unique historical interest as summing up, in the generation preceding the birth of Christ, the religious opinions of the chief schools of ancient thought, and though much in it has been superseded, the main topics with which it is concerned are still the subjects of inquiry and controversy in the modern world.
Last modified April 13, 2016