Hi all!
I’m quite sure this is actually an Abhidharma classification. I’m not aware that it is made anywhere in the Nikāyas, but correct me if I’m wrong. As for the Āgamas, maybe, I don’t know.
I seems to be one of those classifications that are typical to the Abhidharmika approach, certainly that of the Theravadins: to try and fit every teaching into neat categories. In the early suttas I don’t see a clear mind-body separation, however. And there is little to no evidence that nāma was considered purely mental in the early days. It may sometimes be translated as “mentality”, but the word doesn’t mean that, and I don’t think there is good support for that translation. (And note that dictionaries based their definitions on later texts. No existing Pali dictionary is a dictionary of the early vocabulary, unfortunately.)
I don’t agree with the Abhidharma classification, and don’t agree that nāma is purely mental. There are various reasons for that, but we can consider contact (phassa), which is also included in the definition of nāma (e.g. SN12.2). However, to contact—literally to “touch”—some “touchable” with the body, how is that a mental thing?
I also don’t think vedanā is the “(dis)like” attitude towards experience. It is the intrinsic (un)pleasantness of the experience itself. It’s what’s pleasant (sukha), painful (dukkha) or neither.
And as Bundokji already said, there is such a thing as “physical pleasure (kāyika sukha)”. Consider also DN22:
And what is pain? Physical pain, physical unpleasantness, the painful, unpleasant feeling that’s born from physical contact. This is called pain.
And what is sadness? Mental pain, mental displeasure, the painful, unpleasant feeling that’s born from mental contact.
So there is both mental and physical vedanā. I mean, it’s literally called physical/bodily (kāyika) vedanā.
Now, why is vedanā included in the “definition” of nāma? I don’t think “because vedanā is mental” is the answer. Even if vedanā were mental, what exactly would such a definition teach us? And why then use the obscure word nāma instead of citta or alike?
Instead, I think the parts of the definition of nāma underline specific things that consciousness depends on. As taught in Dependent Origination, without nāma(rūpa) there can be no consciousness, and vice-versa. The inclusion of vedāna in nāma therefore teaches that consciousness cannot exist without vedanā, and vice-versa.
However, more importantly, the “definition” of nāma is likely a later addition to the teachings of Dependent Origination. The concept of nāma(rūpa) existed first. As to the core principles of DO, it’s more important to understand what the word nāma itself meant to people of the Buddha’s time, and how this relates to consciousness. Only then should we consider the “definition” that includes vedanā.
I think it would be wrong to see the list of factors as a literal definition of what nāma is. (Perhaps that’s what Bundokji was getting at when he said “reduce all the links in DO to mere designations”.) Rather, it teaches us how to reflect on nāma, and consciousness.
I’ve written about all this more extensively here, for those who are interested.