I find this concept much more explicit in the Theravadan Abhidhamma.
Anyone have a good commentary of the kośa which unpacks it a little?
I did a quick search through the Vyākhyā and didn't see anything that was directly relevant to your query. However, it's possible that I may have missed something.
But at any rate, I don't think there's much difference between how Theravāda and Sarvāstivāda authors regard saṃkalpa. For example, Ghoṣaka's Amṛtarasa states that samyaksaṃkalpa consists of the three skillful thoughts (kuśalavitarka/kuśalasaṃkalpa): the thought of renunciation (naiṣkramya), of non-ill will/non-aversion (avyāpāda), and non-harming (avihiṃsā). This parallels Pāli suttas such as DN 22 and MN 78.
As for the meaning of saṃkalpa, this is a bit more difficult as it's not included in the standard lists of dharmas given under the saṃskāraskandha. Nevertheless, even in the early canonical sources saṃkalpa seems to be related to vitarka (thought), and this association is made more explicit in the Abhidharma. In The Buddhist Path to Awakening
(pp. 193-4), Rupert Gethin offers the following analysis of saṃkalpa:
The root kḷp means “to be in order,” “to be capable,” “to be suitable.” A saṃkalpa is literally, then, a “conforming,” a “(suitable) arrangement or adaptation.” However, the word is regularly used of a clearly formed thought or idea; it thus conveys the sense of “intention” or “purpose.” One might say, then, that saṃkappa is the gearing of the mind to whatever is its object in a definite and particular way. By the time of the early Abhidhamma texts this is clearly identified with the technical term vitakka.... [T]he association of vitakka and saṃkappa is also present in the Nikāyas, though in a fashion that suggests a rather looser connection. The general idea seems to be, then, that saṃkappa is equivalent to the way in which the mind applies itself to or thinks of various objects. Wrong thought turns towards various objects with thoughts and ideas of desire, hatred, or cruelty; right thought turns towards various objects with thoughts and ideas that are free of desire, friendly and compassionate.
I think that "resolve" is generally an adequate English translation of saṃkalpa in many contexts, allowing one to differentiate between saṃkalpa and other important mental factors such as cetanā (volitional intention) and vitarka (thought).
Thanks Jnana. This is quite helpful. I suppose I have found it a little odd that saṃkalpa is not included as a mental factor. The natural conclusion which follows from that would be that it simply implies the combination
of various mental factors - but I find it really strange that it is barely mentioned in the Kośa, considering its centrality. i.e. how important right intention
is in the context of the path, and in the context of karma theory etc.
It seems to me that in the Nikāyas cetanā is usually problematised because it is really the thing driving the whole conditioned process - but might it be the case that cetanā is also an adequate way of accounting for wholesome
trajectories? i.e. saṃkalpa is basically a synonym for a wholesome cetanā?