Vasubandhu’s Twenty Stanzas (Viṃśikā) is among the most influential anti-Realist philosophical treatises in the history of Indian Buddhism. In particular, his refutation of the theories about the accumulation of atoms (paramāṇu) in stanza 12 if often regarded as compelling or even conclusive. But if this is the case, then the transition from stanza 12 to 13 would seem very odd, because in stanza 13 Vasubandhu bothers himself with yet another version of atomic accumulation. In this paper, I give an interpretation (...) of stanzas 12–13 by drawing clues from the Abhidharmakośabhāṣya and Dharmapāla’s Dasheng guangbailun shilun (Taishō 1571). I argue that Vasubandhu’s refutation in stanza 12 is valid only if we assume that the only possible way atoms can accumulate is by means of physical contacts with neighboring atoms. Conversely, if the opponents do not accept this assumption, then Vasubandhu’s refutation would miss its target. Given that stanza 13 cites the theory of the Kāśmīravaibhāṣikas and seeks to refute it, we must interpret that the Kāśmīravaibhāṣikas hold that atoms can form an accumulation in which atoms do not come into physical contact with each other, because this would be the only way to deal with the challenge previously posed in stanza 12. Dharmapāla provides more details about this theory and seeks to refute it again. Assuming the same Vasubandhu to be the author of Abhidharmakośabhāṣya, in which the author deals with the same issue, we must judge that Vasubandhu himself is quite aware of the limitations of his refutation in stanza 12, and this explains why he feels the need to devote stanza 13 to further refuting the theory of the Kāśmīravaibhāṣikas. However, I also argue that Vasubandhu’s refutation of this theory fails. If my argument holds, then we must conclude that the refutation of the accumulation of atoms in the Twenty Stanzas may not be successful. This explains, at least in part, why Dignāga feels the need to find new arguments in his Ālambanaparīkṣā. (shrink)