The Pali word kappa or Sanskrit kalpa is one of those somewhat frustrating terms that appears in a wide variety of senses. The most common sense of kappa in Pali, however, is as an “aeon”, i.e. an unfathomable stretch of time in transmigration.
It’s also used in a psychological sense, usually with a prefix as saṅkappa “thought, intention”, or less commonly parikappa, “plan, proposal”, and so on. The use of the unprefixed form in a psychological sense seems to be restricted to a few verses in the Sutta Nipāta. Ven Bodhi has a nice discussion of this in the introduction to his translation.
As to the exact sense of the psychological meaning, the Niddesa on Snp 5.10:3.2 (verse 1090) gives a good idea of the sense that it means. The question is asked:
Paññāṇavā so uda paññakappī
Is he wise, or does he merely appear wise?
Here kappa as suffix takes the sense of “form, seeming, shape”. The gloss is:
taṇhākappaṁ vā diṭṭhikappaṁ vā kappeti janeti sañjaneti nibbatteti abhinibbattetīti
They construct, generate, produce, give birth to, create craving-construction and view-construction.
So here the sense is clearly of an active process that generates mental processes due to craving and views, and thus is similar or identical to kamma or saṅkhāra. It doesn’t really support the common understanding that kappa here means “thought, notion, figment”: it’s more active than than. Ven Bodhi’s “mental construct” is halfway there; but in psychology a mental construct is a long-term constellation of ideas and beliefs, which—as ven Bodhi acknowledges—is not really captured in his term.
The problem with this passage is that it doesn’t really favor that reading. Norman goes along with the “active” sense, rendering as “is he still acquiring wisdom”. But the commentary and Niddesa, upon which the active reading depend, treat kappa in a purely negative sense; not as the acquiring of wisdom, but as the distorting of it with wrong view and craving. Ven Bodhi rejects the Niddesa and renders according to the more natural sense, “does he have wisdom, or just a wise manner”.
The Niddesa applies the same exegesis to the appearance of kappa elsewhere in the Sutta Nipāta, even though there the word is not a suffix and clearly doesn’t have the sense of “seeming, manner”. So it appears the Niddesa is being overly systematic in its application, treating the word the same way regardless of context. This should give us pause before accepting its readings.
Let us proceed to other contexts and see what we find. There are a few verses in the Sutta Nipāta where the unprefixed form of kappa appears and it has traditionally been understood as “mental construction, ideation, excogitation”. It is explained as being of two types, “excogitations of craving”, and “excogitations of views”. As we have seen, this explanation goes back all the way to the Niddesa, a commentarial commentary. So I’m reluctant to disagree with it. On the other hand, not all contexts it appears in support this reading.
Good method should proceed from the relatively more knowable to the less knowable. In this case, there are a number of mentions where the context is unclear and may be corrupt. So let us start with a more meaningful context.
These are all really rough translations, as I am still figuring out what to do.
In the Sabhiya Sutta at Snp 3.6:15 (verse 517) we have:
Nibbijjha imaṁ parañca lokaṁ,
Having pierced through this world and the next,
Kālaṁ kaṅkhati bhāvito sa danto.
tamed, they bide their time.
Kappāni viceyya kevalāni,
They have examined the kappas (aeons? ideations?) in their entirety,
Saṁsāraṁ dubhayaṁ cutūpapātaṁ;
and both sides of transmigration—passing away and rebirth.
In this verse, the sense of samsara is very strong. “This world and the next” obviously refers to rebirth; “biding their time” is a reference to the arahant awaiting physical death; and the last line needs no explanation.
Here, though the commentary allows kappa in both the sense of “excogitation” and “aeon”, both Bodhi and Norman have favored the psychological reading: “mental constructs” for Bodhi, “figments” for Norman.
Surely, however, the context reads more naturally here as “aeons”. It’s not talking psychologically at all.
Let’s look at another occurrence in Snp 3.6:38 (verse 535):
Chetvā āsavāni ālayāni,
Having cut off defilements and abodes,
Vidvā so na upeti gabbhaseyyaṁ;
Having understood, they do not proceed to another womb;
Saññaṁ tividhaṁ panujja paṅkaṁ,
Having dispelled the three perceptions and the mire,
Kappaṁ neti tamāhu ariyoti.
They do not enter a kappa (cogitation? aeon?): they call that one a “noble one”.
Here the commentary and modern translators all favor the psychological reading. However the context once more invokes rebirth, although here the mention of perception introduces a psychological element as well.
Which is most relevant? Well, notice the syntax:
na upeti gabbhaseyyaṁ …
kappaṁ neti
These are virtually identical: “does not enter into/go to a womb/a kappa”. The psychological translations here are strained: Bodhi has “does not enter upon mental constructs”, while Norman has “he does not come to figments”. It’s an odd idiom; why would you “go into” a mental cogitation?
Here too, then, I think the sense of “aeon” is preferable. Now the meaning is straightforward: they do not go to another aeon, i.e. they do not continue in samsara.
A few verses up at Snp 3.16:21 (verse 521) we find another mention, this one still less clear. Here we find again the identical phrase kappaṁ neti so it would seem that the term is used in the same sense, whatever that is.
Ninhāya sabbapāpakāni,
Having washed off all bad things
Ajjhattaṁ bahiddhā ca sabbaloke;
internally and externally regarding the whole world,
Devamanussesu kappiyesu,
among gods and humans (given to cogitating? trapped in aeons of samsara?),
Kappaṁ neti tamāhu nhātakoti.
the one they call ‘washed’ (does not get involved with cogitating? does not enter another aeon?).
Here Ven Bodhi notes that, while one would expect some connection with the theme of “washing” we don’t seem to find it. So it’s possible that the verse is corrupt. Again, both Bodhji and Norman translate it psychologically (as above), and the commentary only gives the psychological reading.
However if we do a quick search for passages where deva and kappa appear together, we find such phrases as devānaṁ vīsati kappasahassāni āyuppamāṇaṁ “the lifespan of those gods is 20,000 aeons”. While the context itself is not very helpful, surely the same sense can be read here:
Devamanussesu kappiyesu,
among gods and humans trapped in the aeons of samsara,
Kappaṁ neti tamāhu nhātakoti.
the one they call ‘washed’ does not enter another aeon.
Finally, we have one other mention, in Snp 4.10:13 (verse 860), where we once again find kappaṁ neti.
Vītagedho amaccharī,
Free of greed and stinginess,
Na ussesu vadate muni;
The sage speaks not of superior,
Na samesu na omesu,
equal, or lesser;
Kappaṁ neti akappiyo.
Not given to cogitations, they do not enter upon cogitation
Here the context is the three kinds of conceit, and a psychological reading seems preferred. The discourse, “Before the Breakup” is about the realization of a sage before the end of life.
Of course implicit in this is that they have no craving for rebirth, which is made explicit in, for example, verse 856 which speaks of having no craving for existence or non-existence. So it’s certainly not impossible that a cosmological sense is intended.
So it’s all a bit unsatisfactory. Despite the existence of ancient commentaries, the exact sense is hard to pin down. Perhaps the ambiguity in the term confused the ancients as well—it happens! I’m kind of leaning to a cosmological rendering throughout, but I’m really not sure. The fact that the identical phrase kappaṁ neti appears three times does rather strongly suggest that, whatever rendering we choose, it should be consistent across these three cases at least. The first case discussed above is the most clearly cosmological, and there kappaṁ neti does not appear; so perhaps that has a different sense.