The good man, O King, perfect in uprightness, is like a medicine to men and gods, an antidote to the poison of evil. He is like water to men in laying the dust and impurities of evil dispositions. He is like a treasure of jewels to men in bestowing upon them all attainments in righteousness. He is like a boat to men in conveying them to the fur her shore of the four swollen streams – of lust, egotism, delusion and ignorance. He is like a caravan owner to men in that he guides them beyond the sandy desert of rebirths. He is like a mighty rain cloud in that he fills their hearts with satisfaction. He is like a teacher to men in that he trains them in every good. He is like a skilled guide to men in that he points out the path of peace to them.

Milindapanha IV 4, 14 NAGASENA

With the death of Ashoka, the ideal of dharmarajya – the rule of Dharma – passed quickly from Mauryan rule. Though the descendants of Ashoka managed to retain the throne for another half a century, their internecine rivalries and periodic divisions and reunifications of the empire assured a precipitous decline in their fortunes. The last Mauryan emperor, Brihadratha, was deposed by his commander-in-chief, Pushyamitra, who ruled under the title 'general'. At about the time of Pushyamitra's ascension, Bactrian Greeks seized Gandhara and conquered Vahika (the Punjab). Although the succession of Greek kings was as confused as that of the later Mauryans, one monarch, Menandros (Menander to Western historians and Milinda in Buddhist texts), earned a permanent place in the annals of history. As Pushyamitra aged, he supported Brahminical religion and ancient rituals, thereby effectively ending the pervasive influence of Ashoka's magnanimous concept of Dharma. Menandros occupied much of his territory and even marched as far as Pataliputra, where he remained long enough to build a great stupa. When he returned to his capital at Sakala (commonly assumed to be Sialkot in the Punjab), he took the ideal of dharmarajya with him. Buddhist principles became international, spreading from Bactria and the original capital of Menandros at Taxila to central Asia and beyond.

Menandros was admired by both his Greek and Indian subjects for his military genius, his ability to govern fairly, his even-handed support of Greek, Buddhist, Hindu and Zoroastrian traditions, his preservation of economic prosperity and his devotion to the life of the mind. Known to the Greeks as basileus and the Indians as maharaja, he was acknowledged by both as Dharmaraja, the king of justice. His government was Hellenistic in structure, but even while he increased the prominence of the Greek cities originally founded by Alexander the Great, he ensured that the older Indian cities joined them in importance. In later life he cultivated a deep interest in philosophical discussion and reflection, frequently debating thinkers from different traditions and often confounding them with his urbane wit and penetrating insight. Menandros met Nagasena in the course of these debates, was convinced by him, and joined the Buddhist Sangha. He encouraged the dissemination of Buddhist thought throughout his kingdom and built a monastery – the Milindavihara for Nagasena. According to the Milindapanha (The Questions of King Menandros), Menandros renounced his kingdom in favour of his son, entered the monastic community and died an Arhat, having achieved nirvana. Plutarch wrote that he died in camp during a war, but both sources agree that he became a Buddhist. Near the end of his reign he sent a large delegation of monks from Caucasian Alexandria, his birthplace, to attend the consecration of the great stupa at Anuradhapura in Sri Lanka.

According to the Milindapanha, Nagasena was the disciple of Dharmarakshita, the Greek disciple dispatched by Ashoka to Aparanta in western India. Only Nagasena was able to banish the king's doubts and win him over to the Sangha. He was, however, no ordinary monk, for he had been called from transcendental realms to perform this task. The Milindapanha recounts how the king confounded monks and laymen alike and how his words fell upon the mystic ear of Assagutta, an Arhat who dwelt high in the Himalayas. Assagutta convened an assembly of Arhats on the summit of Mount Yugandhara to see if any could match wits with Menandros. When all demurred, Assagutta proposed that they prevail upon the god Mahasena in the heaven of the Thirty-Three. By meditation, the Arhats vanished from Yugandhara and appeared in Sakka's celestial kingdom, and the king of the gods conveyed them to Mahasena's dwelling. Although he initially resisted the request to incarnate in human form, he agreed to do so when it became clear that the principles of religion would be furthered through his Bodhisattvic sacrifice.

When the Arhats returned to their Himalayan abode, they chose one of their number, Rohana, who had been lost in meditation and unaware of the crisis, to act as their agent amongst men. Following their instructions, he journeyed to the village of Kajangala, wherein the wife of the Brahmin Sonuttara had conceived a child. The god Mahasena was born as the boy Nagasena ten lunar months later. Each day for seven years and ten months Rohana begged for food at Sonuttara's house, only to be turned away. Finally the family relented – not knowing that doing so brought an end to Rohana's penance for being lost in meditation when the crisis caused by Menandros' wit had to be met – and the monk received a portion of food each day. At exactly this time Nagasena reached the age of seven and began to study the three Vedas. He penetrated their arcane meanings almost upon hearing them, mastered them and turned to meditation. When he discovered that he had not found the root of reality in his knowledge, Rohana "felt in his mind what was passing in the heart of Nagasena".

Rohana met Nagasena and promised him the secret of reality. Obtaining his parents' consent, Nagasena began instruction under Rohana as a member of the Sangha. Rohana deliberately set the Suttanta (discourses) aside and took up the Abhidhamma (deeper meanings of the faith). When he mastered it in seven months, he was admitted into full membership in the Sangha. But Nagasena doubted the wisdom of his teacher in setting aside the Suttanta, and Rohana at once picked up the thought, which he derided in a thought sent back to the surprised Nagasena. He asked forgiveness, but his teacher withheld it, pending a confrontation with Menandros. Instead, he sent Nagasena to Assagutta for further instruction. Assagutta accepted Nagasena as an attendant and tested him by having him instruct others in the Abhidhamma. Both he and his hearers attained insight as he taught, and Assagutta knew it was time for him to fulfil his destiny. He sent Nagasena to the Ashoka Park in Pataliputra to meet Dharmarakshita.

Dharmarakshita taught Nagasena the outer and inner meanings of the Tripitaka – the three baskets of Buddha's teaching – in six months. The last night of this period witnessed Nagasena's enlightenment, and the earth thundered joyously while the heavens rained sandal dust and mandarava flowers upon the new Arhat. Immediately the Arhats of the Himalayas summoned Nagasena, who vanished from Ashoka Park and appeared before them. They asked him to face Menandros, then they all set out for Sakala, their yellow robes shimmering like lamps and drawing the scented zephyrs of the Himalayan heights along with them.

Nagasena and his illustrious retinue took up lodgings in the Sankheyya hermitage near Sakala, and he was made the chief of the Sangha there.

Learned, with varied eloquence, sagacious, bold,
Master of views, in exposition sound,
The brethren – wise themselves in holy writ,
Repeaters of the fivefold sacred word –
Put Nagasena as their leader and their chief.
Him, Nagasena of clear mind and wisdom deep,
Who knew which was the right path, which the false,
And had himself attained nirvana's heights.

Soon Menandros sent word that he would visit the Sankheyya grove and debate with Nagasena. When the king arrived, he immediately recognized Nagasena by his serene confidence.

At the sight of Nagasena, wise and pure,
Subdued in all that is the best subjection,
Milinda uttered this foreboding word –
"Many the talkers I have visited,
Many the conversations I have had,
But never yet, till now, today, has fear,
So strange, so terrible, o'erpowered my heart."

Menandros did not fear for his safety, but he had a premonition that he had met his match. Since he took his philosophical discussions seriously, he sensed that he would be compelled to accept Nagasena's conclusions, a change of heart that would alter his life.

As soon as polite salutations had been exchanged, Menandros asked how the Thera (Elder) was known. "I am known as Nagasena, O King. . .yet this is only a generally understood term, a designation in common use, for there is no permanent individuality involved in the matter." This answer brought a flood of questions from Menandros.

If, most reverend Nagasena, there be no permanent individuality involved, who is it, pray, who gives to you members of the Sangha your robes and food and lodgings and necessaries for the sick? Who is it who enjoys such things when given? Who is it who lives a life of righteousness? Who is it who devotes himself to meditation? Who is it who attains to the goal of the Excellent Way, to the nirvana of the Arhat? And who is it who destroys living creatures? Who is it who takes what is not his own? Who is it who lives an evil life of worldly lusts, who utters lies, who drinks strong drink, who commits the five sins which work out their bitter fruit even in this life? If there be no permanent individuality, there is neither merit nor demerit, neither doer nor causer of good or evil deeds; there is neither fruit nor result of good or evil karma. If a man were to kill you, there would be no murder. It follows that there are no real teachers or masters in your Sangha and that your ordinations are void.

Thus began a discussion which covered every aspect of Buddhist teaching, replete with rich examples and insights. The discourse as it has been preserved in the Milindapanha is doubtless a crafted compendium of Hinayana doctrine. Nonetheless, the logic of the dialogue and the nature of many of the illustrations suggest that the text may reflect the essence of an historic event, for Menandros is depicted as a skilled dialectician and Nagasena is portrayed as a master of Buddhist thought.

When Nagasena asked if the axle or the pole, the wheels or the frame, the ropes or the yoke, was the king's chariot, he answered that it was none of these things nor all of them together. "It is on account of having all these things that it comes under the generally understood term 'chariot'." "Just so", Nagasena explained, "do I come under the generally understood term 'Nagasena'." Generally expressed, a thing or individual is a temporary matrix of skandhas – aggregates of elements – and therefore there is no metaphysical difference between general and proper nouns. Nagasena elaborated the doctrine of dependent origination, using the example of the king and his shadow, to show that everything depends on something else for its existence. Having won the king's undivided attention, he laid down a requirement for further discussion. The king must discuss as a pandit, or scholar, and not as a king, for monarchs simply reject those who do not agree with them, whereas scholars acknowledge errors and accede to superior reasoning. Menandros agreed, and Nagasena undertook to come to Sakala regularly for discussions.

"Let our discussion be about the truth", Menandros proposed, and then asked about the aim of the Sangha. "Our renunciation is to the end that sorrow may perish and that no further sorrow may arise", Nagasena explained, pointing out that not all monks joined the order with such lofty motives. Reincarnation could be avoided, he taught, only by reasoning and by wisdom, for "reasoning has comprehension as its mark, but wisdom has cutting off.... The recluse by his thinking grasps his mind and by his wisdom cuts off his failings." In addition, five other qualities have to be acquired: good conduct (shila), faith (shraddha), perseverance (virya), mindfulness (sati) and meditation (samadhi). Nagasena quoted Buddha to show that shila was the basis of the whole of the Path:

Virtue's the base on which the man who's wise
Can train his heart and make his wisdom grow.
Thus shall the strenuous bhikku, undeceived,
Unravel all the tangled skein of life.

If the mark of virtue is the presence of all good qualities, the mark of faith is tranquillity and that of perseverance is rendering support; that of mindfulness is recollection and presence of mind; that of meditation is being the leader which marshals the other qualities to one end or goal; and that of wisdom is both cutting off and enlightenment.

When wisdom springs up, O King, it dispels the darkness of ignorance; it causes the radiance of knowledge to arise; it makes the light of intelligence shine forth; and it makes the Noble Truths plain.

For Nagasena, intelligence is the same as wisdom, and so an individual who will not reincarnate again invariably knows it because he is aware of the cessation of the causes of rebirth, for only namarupa, name and form, suffers rebirth and the Arhat no longer identifies with either. Rupa includes everything that is gross and nama all that is subtle and mental. They arise together, and where they are found, time appears, and with time, reincarnation. The Arhat, free of rebirth, does not experience time, whose root is avidya, ignorance.

By reason of ignorance came the samskaras (forces or potentialities), by reason of the samskaras consciousness, by reason of consciousness namarupa, by reason of namarupa the six organs of touch (eye, ear, nose, tongue, body and sensory mind), by reason of them contact, by reason of contact sensation, by reason of sensation thirst, by reason of thirst craving, by reason of craving becoming, by reason of becoming birth, and by reason of birth old age and death, grief, lamentation, sorrow, pain and despair.

In setting out the twelve nidanas, or links in the circular chain of dependent origination, Nagasena showed that there was no apparent beginning or ending to the sequence. He used the example of the hen and the egg to illustrate his point. Since the chain cannot be exhausted, there is no immortal soul to be found within it. The chain must be broken by appeal to the ground in which it arises, and that is enlightenment.

Having been introduced to the Buddhist standpoint, Menandros retired to study the scriptures and to ponder what he had been taught. His skill in and fondness for debate impelled him to test Nagasena by confronting him with apparently contradictory doctrines and injunctions from the sacred texts. Nagasena responded to some of these dilemmas by explication, some by argumentation, and some by showing that the statements had to be understood in their context. Since Nagasena readily admitted a gap between the ideals of the Sangha and the practices of many of its members, Menandros refrained from formulating the chasm between ideal and reality as a dilemma. On one occasion, Menandros confronted Nagasena with a text from the Jataka which enjoined non-violence and another text which exhorted: "Punish him who deserves punishment, favour him who is worthy of favour." Nagasena patiently explained that the maxim of non-violence is derived from the nature of the Dharma, whereas the second passage has a specific application.

The proud heart, great King, is to be subdued, and the lowly heart cultivated; the wicked heart is to be subdued, and the good heart to be favoured; carelessness of thought is to be subdued, and exactness of thought to be nurtured.

Menandros was troubled by the Buddhist emphasis on feeling love for all beings, because he could think of numerous instances where love had resulted in tragedy for either the lover or the beloved. Nagasena explained that love which was focussed on an object could result in a variety of consequences – good, bad or indifferent – but that love without an object is universal and not the attribute of any individual.

The virtues of love are not attached to the personality of the one who loves, but to the actual presence of the love that one has invoked in his heart. . . . At the moment in which an individual has realized this sense of love, neither fire nor poison nor sword can do him harm.

Menandros posed eighty-two dilemmas to Nagasena, who responded to each to the satisfaction of the king. No longer did Menandros wish to debate for argument's sake, nor to test Nagasena's skill and knowledge. Rather, he wished to learn from a teacher whose wisdom was proven, and his questions became those of a disciple who was open and receptive to understanding.

Nagasena developed an elaborate metaphor for the Sangha – Buddha's City of Righteousness.

The Blessed One's City of Righteousness, O King, has righteousness for its rampart, fear of wrongdoing for its moat, knowledge for its battlement, zeal for its watchtower, faith for its pillars, mindfulness for the watchman at the gate, wisdom for the terrace above, the Suttantas for its market-place, the Abhidhamma for its crossways, the Vinaya (law) for its judgement hall, and constant self-possession for its chief street.

Its flower bazaar consists of the subjects for meditation, and its perfume bazaar is the virtues. Its fruit bazaar is composed of the results of each stage of its Path, whilst its antidote bazaar contains the medicaments of the Four Noble Truths. Its medicine bazaar holds the means of mindfulness and the powers of morality and wisdom; its ambrosia bazaar is meditation upon the Real. Its jewel bazaar contains the seven priceless gems of right conduct, meditation, knowledge, emancipation, insight, discrimination and the sevenfold wisdom of the Arhats. The City can be seen by those who have cultivated eyes to see; it is both the foundation of the Sangha and the proof of the reality of Buddha.

Having shown the nature and meaning of Buddha, the Dharma and the Sangha, Nagasena offered one hundred and five similes of the ideal monk and Arhat. For example, the bhikshu should be like the earth in remaining the same, being self-perfumed, standing firm, never wearying, and being free of ill-will towards others. Like water, he should be pure, refreshing, free from offence, much desired by the world and harmless. Like fire, he should burn away everything unnecessary and undesirable, show no pity towards his inclinations, light up his heart into a purifying blaze, benefit all beings and dispel darkness. Like the wind, he should penetrate the groves of meditation, bend everything before his examination, be above all earthly concerns, bear good qualities along with himself and yet remain homeless in the world. Just as space cannot be grasped, so too the bhikshu should elude the grasp of every desire; like space, the effort of the bhikshu should know no limit; and like space, he should depend on nothing outside himself.

According to the Milindapanha, Menandros asked Nagasena three hundred and four different questions, which resulted in his complete acceptance of the Teachings of Buddha. Whether he became a monk near the end of his life, as the Milindapanha declares, or remained a lay disciple, as Plutarch implies, he ruled with a wisdom and detachment that earned him a unique place in Greek and Indian history. Nothing is known of Nagasena after his lengthy encounter with the king. This seems altogether appropriate, for he had been called into mortal existence for the sake of the Dharma, and, having performed his task, he vanished from the attention of history. Yet he left behind a method of explicating the Teaching of Buddha which became the archetype of subsequent elucidation. His subtle blend of metaphysics and ethics, argument and example, produced a model of useful discourse and an encouragement to practice. The Milindapanha is unique in being revered by Hinayana and Mahayana alike. Its depictions of the Path and the Goal have been relevant to every succeeding generation, for it is above all a portrait of the Arhat.

He strives with might and main along the Path, searches it out, accustoms himself to it; to that end does he make firm his self-possession, to that end does he hold fast in effort, to that end does he remain steadfast in love towards all beings in all worlds; and still to that does he direct his mind again and again, until gone far beyond the transitory, he gains the Real, the highest fruit. And when he has gained that, the man who has ordered his life aright has realized nirvana.

Milindapanha IV 8, 84