Subjects of Experience and Subjective Perspectives

Split-brain subjects may have two distinct subjects of experience, one per hemisphere, because consciousness is unified within each hemisphere but not across them. The empirical basis is that elements of experience are present in both hemispheres yet are not integrated between them. This suggests each hemisphere has its own subjective perspective, making it impossible for a single subject to have multiple perspectives in the same way another subject has one. Therefore, the two hemispheres likely correspond to separate subjects of experience, each related to its perspective as a normal person is to theirs.

Study at a glance

Abstract

This chapter offers a preliminary defense of the claim that the two hemispheres of a split-brain subject are associated with distinct subjects of experience. The empirical basis of this 2-subjects claim is that, while both hemispheres are the source or site of elements of experience, these elements are unified only within each hemisphere system, and not across them. In other words, consciousness is unified intrahemispherically, but disunified interhemispherically. A split-brain subject thus has two subjective perspectives, one associated with the right hemisphere and one with the left. Our first-personal way of understanding what it is to be an experiencing subject, however, makes it impossible for a single subject of experience to have multiple subjective perspectives in just the same way that another subject of experience has one. It seems to follow that the two hemispheres of a split-brain subject are associated with distinct subjects of experience, each standing in just the relation to its one perspective that I do to mine.