was asked a question of a metaphysical kind, he remained 252 Lele, The Metaphysical Basis of Śāntideva's Ethics silent. He directed his disciples toward practical efforts. . . Life is short; it must not be spent in endless metaphysical speculations which will not be able to bring the truth. (Nhat Hanh 38–39) One can find this remark of Nhat Hanh's quoted all over the Internet. And there is a similar interpretation in Taitetsu Unno's River of Fire, River of Water: This inability to know extends to metaphysical truths. In the famous parable of the poison arrow found in early Buddhism, a young monk, Malunkyaputta, is unhappy because the Buddha refuses to answer metaphysical questions. They include fourteen unanswerable questions, such as whether the universe is finite or not,the traditional Western conception of philosophy as an interconnected system of theoretical and practical philosophy, like Aristotle's or Kant's.8 Śāntideva is not alone in his use of metaphysics as a foundation for ethical claims. Most notably, the Bodhicaryāvatāra's connection of metaphysics to ethics has close resonances to the "four illusions" with which Karen Lang titles her translation of Candrakīrti's commentary on Āryadeva's Catuḥśataka. These, too, are metaphysical errors which lead to ethical missteps. Āryadeva's list of metaphysical errors-perceiving the impermanent as permanent, the painful as pleasant, the impure as pure and the non-self as self-is a widespread Indian list of four "inversions" (viparyāsa or vipallāsa). The list of four goes back at least to the Pāli Paṭisambhidāmagga, with a related formula in the Aṅguttara 8 Others have often