I have to excuse myself I am not an abhidhamma-scholar even though I would like to learn more about it. In what way does the Patthana provide solutions to the problems pointed out by Waldron? I am by the way not very found of american scholarship simply out of the reason of the sometimes low quality of the philological base of their research, and I would not be too surprised to see that Waldron's publication suffer the same shortcomings. Mainly for the reason that he did publish a very euphoric review of a publication of Dan Lusthaus which I, after going through it with some care, have to dismiss as quite weak when it comes to the understanding of the used source languages.
But this has in my eyes nothing to do with the research subject (mahāyāna buddhism), but rather with the specific climate of the universities. Japanese and continental european scholars usually pay much more attention to the philological base and are also less prone to philosophic speculation, which in my eyes is the way to go.
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