This dissertation offers a new interpretation of the Monograph in Twenty Verses, an important essay in the history of philosophy in South Asia by the influential Buddhist philosopher Vasubandhu (fl. fifth century CE). I argue that Vasubandhu should be read as promoting a view that intentionality is not a function of the causal influence of material (or other ersatz) objects on us, but rather is just what living beings’ habituation to species-specific and species-neutral patterns of activity “looks like.” Against the grain of contemporary interpretations of Vasubandhu and the bulk of Buddhist and Brahmanical commentary after the sixth century CE, I show that Vasubandhu’s thesis amounts to a rejection of empiricism, if this is understood, minimally, as the thesis that perceptual knowledge is an independent and foundational epistemic criterion. Instead, Vasubandhu conceived of his essay as a rational reconstruction of the Buddha’s claims, importantly arguing against both empiricist intuitions in epistemology and the adequacy of the kind of phenomenalism typically encouraged by empiricism when specifying the nature of mental events. The concept of habituation advanced by Vasubandhu, grounded in ideas developed through the history of Buddhist debates in cosmology, biology, and physics, is an exemplary instance of Vasubandhu’s ideas, which were not easily accommodated by empiricist philosophers in the Buddhist tradition writing in his wake.
In effect, the dissertation seeks to recuperate a paradigm of philosophical inquiry for Vasubandhu distinct from the kind of epistemology which served as the dominant paradigm for philosophers in South Asia after the sixth century. A form of inquiry prominent from the first to the fifth centuries of the common era—and a paradigm termed “natural philosophy” or perhaps “metaphysics as natural philosophy”—is the most helpful way of characterizing the background of Vasubandhu’s arguments and concerns. I offer an interpretation of the Twenty Verses that foregrounds two concerns exemplary of what I am calling natural philosophy: firstly, the long and neglected history of Buddhist debates concerning cosmology; and secondly, debates concerning the atomic constitution of material objects.