Nāgasena's chariot

What it tests Is a person, like a chariot, nothing over and above its parts arranged in a certain way, and if so can there still be someone who acts and is responsible?

The case

Milinda, usually identified with the Indo-Greek king Menander I, asks the Buddhist monk Nāgasena what he is called. The monk replies that he is called Nāgasena, but that this, like any such name, is “only a generally understood term, a designation in common use”, for “no permanent individuality (no soul)” is involved. The king objects. If there is no such individuality, who gives the monks their robes, who lives righteously, who kills? There would be neither merit nor demerit.

Milinda then asks whether Nāgasena is the hair, the nails, the bones, the blood, or the five aggregates (skandhas in Sanskrit): form, feeling, perception, mental formations and consciousness. Is he all of these together, or something apart from them? To each question the monk answers no, and Milinda concludes that Nāgasena is “a mere empty sound”.

Nāgasena turns the question round. How did the king come, on foot or by chariot? By chariot. Is the chariot the pole, the axle, the wheels, the framework, the yoke, the goad? Is it all of them together, or something apart? No to each. “Chariot is a mere empty sound”, the monk says, and accuses the king of untruth. Milinda replies that it is “on account of its having all these things” that it “comes under the generally understood term, the designation in common use, of ‘chariot.’” Nāgasena agrees: the same holds for him. He then quotes the nun Vajirā: “Just as it is by the condition precedent of the co-existence of its various parts that the word ‘chariot’ is used, just so is it that when the Skandhas are there we talk of a ‘being.’”

What it is meant to show

The chariot illustrates anattā, the Buddhist teaching that no permanent, unchanging self is found in a person. On the usual reading, a person is a name for a causal series of physical and mental events, the five aggregates, arranged in a certain way. The chariot is Nāgasena’s answer to Milinda’s objection: a chariot is real enough to ride in, and a conventionally real person is real enough to give, to act and to be answerable. Later Buddhist philosophers called this the distinction between conventional and ultimate truth, and the chariot became its stock example.

The verse comes from an older source, the Saṃyutta Nikāya (SN 5.10). The Milindapañha is later: scholars date its earliest part to between about 100 BCE and 200 CE, and it is canonical in Burmese Buddhism but not in Thai or Sri Lankan Buddhism.

Replies

Abhidharma reductionism. The Abhidharma schools developed the argument into an ontology. The ultimately real things are momentary physical and mental events (dharmas), and anything that can be broken into parts, chariots and persons included, is conventionally real. Whether this makes persons useful fictions, as Mark Siderits argued, or something stronger, as Monima Chadha argues of Vasubandhu, is disputed.

The personalists. The Pudgalavādins held that the person is real, neither the same as the aggregates nor different from them, and “inexpressible”. They wanted a bearer of karma and responsibility, and their Buddhist opponents thought this contradicted no-self.

Madhyamaka. Nāgārjuna, who founded the Madhyamaka school, denied that the person is the same as the aggregates or other than them. Candrakīrti, in the seventh century, turned the chariot against the Abhidharma use of it, examining it in seven ways and finding no inherently existing chariot in any. On Dhivan Thomas Jones’s reading this is a guide to meditation, not a theory of self or no-self.

Nyāya. Nyāya and Vaiśeṣika philosophers held that the self is a distinct substance, inferred from desire, cognition and action, and used a chariot too: we infer the driver from the chariot’s movement. Buddhists answered that such a self would be causally idle. The chariot of the Kaṭha Upaniṣad is a different image, of how the self, body, mind and senses relate.

A critic can also ask whether the analogy holds for a subject of experience, since a chariot has no point of view on its own parts. The reductionist must then say what a point of view is in a causal series of events.

Variations

In Book II, chapter 2, Milinda asks whether one who is reborn is the same as the one who died. “Neither the same nor another”, Nāgasena answers, and gives two images. A lamp burns through the night, but the flame of the first watch is not the flame of the second, and yet there is not a different lamp in each. Milk becomes curds, butter and ghee, not the same as the milk but produced out of it. The images describe identity as a continuity of events, a Buddhist cousin of the ship of Theseus.

Why it still matters

David Hume described the mind as a bundle of perceptions. Siderits called the Abhidharma position reductionism, the word Derek Parfit used for his own view that persons exist only in the way nations do. The question has taken a new form for software that can be copied, paused and resumed, which I discuss in If a mind can be copied, is it the same mind?