The following is a comment I wrote some time ago in the discussion thread on this article. I’ve extracted it and reposted here, with a couple of minor changes.

To understand the famous passage on the “radiant mind” we will have to go into some details and background, so hold on. Here’s the Pali:

51. ‘‘Pabhassaramidaṃ , bhikkhave, cittaṃ. Tañca kho āgantukehi upakkilesehi upakkiliṭṭhaṃ. Taṃ assutavā puthujjano yathābhūtaṃ nappajānāti. Tasmā ‘assutavato puthujjanassa cittabhāvanā natthī’ti vadāmī’’ti. Paṭhamaṃ. 52. ‘‘Pabhassaramidaṃ , bhikkhave, cittaṃ. Tañca kho āgantukehi upakkilesehi vippamuttaṃ. Taṃ sutavā ariyasāvako yathābhūtaṃ pajānāti. Tasmā ‘sutavato ariyasāvakassa cittabhāvanā atthī’ti vadāmī’’ti. Dutiyaṃ.

The sutta appears in the middle of a long list of other short suttas, all of which deal with some aspect of mental development, eg. metta and so on. These texts are obviously artificial in a sense: they have been divided up from longer, more coherent discourses to fit the “Ones” format. Thus these two “suttas” are really one sutta; and the same goes for the two previous suttas (not quoted here), which are just abstracts from the present text.

The overall context of this part of the Suttas is samadhi: in fact, probably the reason these texts have been artificially “processed” to fit in this section is because the idea of “one” fits well with samadhi as “one-pointedness of mind”. This doesn’t prove anything, but it does suggest that we should expect texts here to deal mainly with samadhi.

A literal translation is:

Radiant, monks, is this mind. And it is defiled by transient defilements. An unlearned ordinary person does not understand that in accord with reality. Therefore I say, “An unlearned ordinary person does not have mental development.” Radiant, monks, is this mind. And it is freed from transient defilements. A learned noble disciple person understands that in accord with reality. Therefore I say, “A learned noble disciple has mental development.”

The syntax of the sutta is somewhat obscure, in Pali as in English: while there are no grammatical difficulties, it is not entirely clear what the sense of the text is. This is already a red flag: as a rule, one should never rely for crucial explanations on a text that appears only once, and which is unclear. Surely in a crucial matter the Buddha would have stated it many times and made it clear what he was talking about. As a rule, when faced with an obscure passage, we look to more clear examples to help us understand.

To start with, then, let’s look at other Sutta passages that use the same word “pabhassara”. Here I will ignore the fact that this word is merely a synonym for many other terms such as abha, pariyodata, obhasa, and so on, that are frequently used in the context of samadhi. A quick search of the uses of pabhassara reveals this:

Majjhima 93 Assalayana: the “radiance” of a fire

Samyutta 6.5: The “radiance” of Brahma

Samyutta 46.31–32: The “radiance” of gold, compared to the “radiance” of the mind when it has right samadhi (i.e. jhana).

Samyutta 51.22: the Buddha’s body in samadhi is lighter and “more radiant”, like hot metal.

Anguttara 3.101: Similar to SN 46.31 above, except here the word pabhassara is only directly used in the simile when referring to gold; the text goes on to speak of samadhi, but doesn’t use pabhassara. However,

Anguttara 3.102: Here pabhassara is used of samadhi, in the same stock phrase as above, as well as in the “gold” simile.

Anguttara 5.23: “Gold” and “samadhi” as above.

Sutta Nipata 46: “Radiant” gold jewellery.

So pabhassara is used in an ordinary language sense of the “radiance” of a fire or gold; in a “religious” sense of the light of Brahma; and in a Dhamma sense of the radiance of the mind in samadhi. The sense of the simile of gold, which is the most common context, is that just as gold has impurities and the smith will gradually work them out, resulting in pure, radiant gold, so too the meditator eliminates the defilements (upakkilesa = nivarana = 5 hindrances) and thereby leads the mind to samadhi. This all hangs together very straightforwardly. Nowhere is there any suggestion that it has anything to do with Nibbana.

These passages, especially the recurring comparison of gold with samadhi, are clear and well-defined. They are proper teachings, not just cut-up slivers with no parallels, as in the more famous pabhassara citta passage. This is one of the most common tendencies we find in Buddhist history: that well-known, frequently repeated passages with clear meaning are ignored, while obscure, marginal passages, probably suffering severe editorial loss, are taken up precisely because their obscurity allows one to read anything into them.

Returning to our passage, the “radiant” mind is said to be either defiled or freed from defilements. While the overall context is cittabhavana, i.e. samadhi, and is obviously meant to be the same as the more common gold/samadhi passage, there is a crucial difference. That is, in the gold/samadhi passages, the gold (and the mind) is said to be “not radiant” when it is defiled; and “radiant” when the defilements are removed. But the texts under discussion say exactly the opposite.

There is a clear contradiction here, and as always, one can approach contradictions in various ways. Perhaps the two can be harmonized: the radiance of the mind is potentially there, even if not apparent. Fine, but that is not really how the Buddha talked about things. We should always prefer a simpler, more grounded explanation, not one that necessitates revising the whole of the Buddha’s teachings based on one dubious passage. Given that the text has obviously suffered editorial changes, I suspect that the problems arose due to these.

The beginning of the Sutta has the Buddha (presumably, although it doesn’t actually say so), saying, “This mind is radiant…” The particle “idam”, “this”, functions to limit and specific: This mind, not “the mind” (as in Thanissaro’s translation). As well as the gold/samadhi passages, we might compare to the Upakkilesa Sutta, where the Buddha speaks of how he meditated, then light arose, but because of “defilements” (upakkilesa, the same word as our sutta), the light vanished. The word for light is different (obhasa), but is from the same root with the same basic meaning.

This is the normal way the Buddha talked about the mind. It is not that it is “naturally” radiant or defiled: it is naturally conditioned. When the conditions for darkness are there, it is dark, when the conditions for light are there, it is light. Our passage, which is unique, without parallels in any early Suttas, syntactically awkward, clearly the subject of editing, can be read as suggesting a different take on things, that the mind is somehow “radiant” even when covered by defilements. Or it can be read in line with the other, more clear suttas.

In either case, there is no suggestion here that the “radiant mind” be connected with Nibbana. Quite the opposite: the whole point of the sutta is that it can be defiled, so it cannot be Nibbana.