The Platonic corpus includes a series of striking portraits of Sokrates at work using a method commonly referred to as “the elenchus.” “Elenchus” (testing, interrogation, refutation) is only one of the words used by Plato for Sokrates' activities, and its use as a technical term has become contested. But it is not necessary to commit oneself to a specific or technical account of his methods in order to identify the elenctic Sokrates, with reasonable clarity, as the figure of the Apology, who tests those reputed to be wise, affirms his own ignorance, and reaches few, if any, positive results. Whatever term we choose to describe his use of question and answer, it functions as “a gadfly-sting designed to instill aporia in his interlocutors, to stir up the appetite for philosophy, and to show the audience (including the readers) that those who pretend to wisdom … are not really wise.”

Plato's techniques for characterization are particularly important in his representations of this figure at work, not just because of Sokrates' own peculiarities but because of the ad hominem nature of his approach, which makes the dramatic delineation of his interlocutors especially significant. This Sokrates examines not just arguments but individual people, in ways that cast doubt not merely on their beliefs, but on the personality, way of life, and social roles that condition those beliefs and are in turn conditioned by them. His method is therefore intrinsically ad hominem in a peculiarly personal way.

For helpful comments on the Introduction and notes I am very grateful to Desmond Clarke, Hilary Gaskin, Raphael Woolf, Daniel Russell and Alison Futrell. I am especially grateful to Alison Futrell, my colleague in Roman History, for help with a number of Roman issues, from the Voconian law to the excess, in this work, of members of the Licinius Crassus family called Marcus. I also owe thanks to all the students, graduate and undergraduate, to whom I have taught this work in my courses on ancient ethics, and who have helped me come to see the difficulties it presents for a modern reader. I am grateful for the work of scholars who have, in the last decades, produced new translations of important texts from the Hellenistic or post-Aristotelian period of ancient philosophy, and have helped in the process of making the theories of the Stoics, Epicureans and even eclectics like Antiochus part of the normal syllabus in ancient philosophy. I hope that this new translation and edition will make Cicero's text more accessible to a wide audience interested in ancient ethics.

It has been a pleasure to work with Raphael Woolf, who has produced a translation which is not only philosophically accurate but also stylish in Cicero's manner without expanding the English to twice the length of the Latin.

(1) I had been listening, Brutus, as I often did, to a lecture by Antiochus with Marcus Piso. It took place in the public building known as the Ptolemaeum. With us were Quintus my brother, Titus Pomponius and Lucius Cicero, whom I loved like a brother, though we were actually cousins.

We decided to take our afternoon stroll in the Academy, mainly because there would be no crowds at that time of day. We all met at Piso's place, at the appointed hour, and occupied ourselves with various topics of conversation on the walk, just over half a mile, from the Dipylon Gate. We arrived at the Academy's justly famous grounds to find that we had the place to ourselves, as we had hoped.

(2) Piso then remarked: ‘I cannot say whether it is a natural instinct or a kind of illusion, but when we see the places where we are told that the notables of the past spent their time, it is far more moving than when we hear about their achievements or read their writings. This is how I am affected right now. I think of Plato, who they say was the first philosopher to have regularly held discussions here. Those little gardens just nearby not only bring Plato to mind, but actually seem to make him appear before my eyes.

(1) In this work I am putting into Latin themes which philosophers of the highest talent and most refined learning have dealt with in Greek, and I am well aware, Brutus, that this will incur criticism of various kinds. Some people, by no means uneducated, altogether disapprove of philosophizing. Others do not criticize it so long as it is done in an easygoing manner, but consider that one should not devote so much of one's enthusiasm and attention to it. There will also be people, learned in Greek and contemptuous of Latin, who say that they would rather spend their time reading Greek. Finally, I suspect that there will be some who will call on me to follow other literary pursuits, claiming that this kind of writing, however elegantly done, is none the less not worthy of my character and position. (2) Against all of these critics I think that some brief reply ought to be made.

To those who pour scorn on philosophy I made an adequate response in the book in which I defend and laud philosophy against the accusations and attacks of Hortensius. This book appeared to please you and all those whom I consider competent to judge, and so I undertook to write more, fearing that otherwise I might be perceived as exciting people's enthusiasm but unable to sustain it.

(1) If pleasure lacked such tenacious advocates, Brutus, and spoke for herself, I think the previous book would compel her to concede defeat to real worth. How shameless she would be to resist virtue any longer, to prefer what is pleasant to what is good, or to contend that bodily enjoyment and the mental delight that it causes are of more value than a steadfast seriousness of purpose.

So let us dismiss her and order her to stay within her own borders. We do not want the rigour of our debate to be hampered by her seductive charms. (2) We must investigate where that supreme good that we want to discover is to be found. Pleasure has been eliminated from the inquiry, and pretty much the same objections hold against those who maintained that the ultimate good was freedom from pain. Indeed no good should be declared supreme if it is lacking in virtue, since nothing can be superior to that.

We were forceful enough in our debate with Torquatus. But a still fiercer struggle with the Stoics is at hand. The topic of pleasure militates against really sharp or profound discussion. Those who defend pleasure are not well versed in argument, and her opponents are confronting a case that is not hard to refute. (3) Even Epicurus himself said that pleasure is not a matter for argument, since the criterion for judging pleasure is located in the senses.

(1) At this point they both looked at me and signalled that they were ready to hear me. I began by saying, ‘Let me first of all beg you not to expect me to expound a formal lecture to you like a philosopher. Indeed this is a procedure I have never greatly approved of even in the case of philosophers. After all, when did Socrates, who may justly be called the father of philosophy, ever do such a thing? It was, rather, the method of those known at the time as sophists. Gorgias of Leontini was the first of their number bold enough, at a public meeting, to “invite questions”, that is, to ask anyone to name a topic for him to speak on. A daring venture – I would have called it impudent, had this procedure not been adopted later by our own philosophers.

(2) ‘But we know from Plato that Gorgias and the other sophists were mocked by Socrates. Socrates’ own technique was to investigate his interlocutors by questioning them. Once he had elicited their opinions in this way, he would then respond to them if he had any view of his own. This method was abandoned by his successors, but Arcesilaus revived it and laid it down that anyone who wanted to hear him speak should not ask him questions but rather state their own opinion. Only then would he reply.

In June 45 Marcus Tullius Cicero composed On Moral Ends, a treatment in three dialogues, over five books, of fundamental issues of moral philosophy. The sixty-one year old Cicero, a Roman statesman with an eventful and distinguished career, had gone into political retirement during the ascendancy to supreme power of Julius Caesar after a turbulent period of civil war, in which Cicero had ended up on the losing side. His personal life had also fallen apart. In 46 he divorced Terentia, his wife of thirty years, and married his young ward Publilia. The marriage broke up less than a year later, partly because of Cicero's extreme sorrow at the death in childbirth of his much–loved daughter Tullia, together with her baby, in February 45. A productive writer, he decided to use his enforced and grief-stricken leisure to introduce educated Romans to major parts of the subject of philosophy in their own language, rather than leaving them to read the originals in Greek. On Moral Ends is the most theoretical of the works on moral philosophy, accompanied by more specialized discussions in On Duties and Tusculan Disputations and the more ‘applied’ Friendship, Old Age and Reputation.

On Moral Ends is a substantial work of moral philosophy. There have been periods when it has been an influential part of the discourse of moral theory, and it has always been a valuable source for the three moral theories it discusses, those of Epicurus, the Stoics and Antiochus (the last a hybrid influenced by Aristotle).

(1) With that, Cato concluded his discourse. ‘For a theme so large and obscure’, I said, ‘your exposition was as accurate as it was lucid. Either I should altogether give up on the idea of responding, or else at least take some time out for reflection. In both its foundations and in the edifice itself Stoicism is a system constructed with great care; incorrectly, perhaps, though I do not yet dare pronounce on that point, but certainly elaborately. It is no easy task to come to grips with it.’

‘Is that so?’ Cato replied. ‘In court I see you, under this new law, delivering the case for the defence on the same day and finishing up within three hours. Do you think I am going to grant you a deferral in this case? Mind you, you will find your brief no sounder than some of those you occasionally manage to win. So handle this one in the same way. Others have, after all, dealt with the topic, as you have yourself often enough, so you cannot be lacking in material.’

(2) To this I replied: ‘Steady on! I am not in the habit of mounting reckless attacks on the Stoics. I am by no means in complete agreement with them, but humility restrains me: there is so much in Stoicism that I barely understand.’ ‘I admit’, said Cato, ‘that there are some obscure elements.