The Madhupiṇḍika Sutta, MN 18, is one of the most subtle and interesting texts of the whole canon. It was famously the basis of Nyanananda’s seminal Concept and Reality, and has received commentary from pretty much every serious Buddhist teacher since then. Here, as usual in this series, I won’t attempt to delve into the philosophical issues, but to clarify the translation.
The key difficult is the compound papañcasaññāsaṅkhā. Since this is a compound, and is not verbally analyzed, grammar is of limited use, and we must rely on context. The key is to understand the relation between the terms. Since this has been translated many times, I will leave aside former translations and simply explain the logic I use.
Let’s start with what we do know. Saññā is said to “underlie” this process. And in the more detailed explanation below, saññā occurs before papañca in the series. Thus we are on solid ground in treating saññā in this case as a precursor to papañca. They are not equal partners; one leads to the other.
As for saṅkhā, this occurs only at the very end of the sequence. Significantly, it appears only in the same phrase as the purisa, the “person”. The normal sense of saṅkhā is what something is “reckoned” as. It’s not a mere concept in a neutral sense, but an expression of identity. Thus at the end of the sequence, the “person” is beset with such notions of identity, a “self” that persists through the three periods of time.
Hence saññā is subject to a process of papañca whose outcome is the saṅkhā of a self. I therefore suggest translating the phrase:
purisaṃ papañcasaññāsaṅkhā samudācaranti
A person is beset by concepts of identity that emerge from the proliferation of perceptions.
This is basically similar to the first of the alternative translations suggested by Ven Bodhi in his note on this passage.
I have translated thusly the extended passage in Mahākaccāna’s explanation :
Eye consciousness arises dependent on the eye and sights. The meeting of the three is contact. Contact is a condition for feeling. What you feel, you perceive. What you perceive, you think about. What you think about, you proliferate. What you proliferate about is the source from which a person is beset by concepts of identity that emerge from the proliferation of perceptions. This occurs with respect to sights cognizable by the eye in the past, future, and present.