This paper examines Sartre's dualistic ontology in the light of the non-duality asserted by Mahayana Buddhism. In the first section, I show, against the objection of Hazel E. Barnes, that Sartre and Buddhism have comparable theories of consciousness. The second section discusses Steven W. Laycock's use of Zen philosophy to solve the Sartrean metaphysical problem regarding the origin of being for-itself. This solution involves rejecting the ontological priority of being in-itself in favor of the Buddhist understanding of interdependent origination (pratitya-samutpada) (...) and emptiness (sunyata). Finally, I explain how this aspect of Buddhist thought is consistent with Sartre's ontology, thus making an acceptable solution. This consistency is possible if we understand Sartre's ontology as provisionally true in a sense gleaned from the Madhyamika and Yogacara schools of Indian Buddhism, which were influential to the formation of Zen philosophy. (shrink)