This book explores a neglected philosophical question: How do groups of interacting minds relate to singular minds? Could several of us, by organizing ourselves the right way, constitute a single conscious mind that contains our minds as parts? And could each of us have been, all along, a group of mental parts in close cooperation? Scientific progress seems to be slowly revealing that all the different physical objects around us are, at root, just a matter of the right parts put (...) together in the right ways: How far could the same be true of minds? This book argues that we are too used to seeing the mind as an indivisible unity and that understanding our place in nature requires being willing to see minds as composite systems, simultaneously one conscious whole and many conscious parts. In thinking through the implications of such a shift of perspective, the book relates the question of mental combination to a range of different theories of the mind (in particular panpsychism, functionalism, and Neo-Lockeanism about personal identity) and identifies, clarifies, and addresses a wide array of philosophical objections (concerning personal identity, the unity of consciousness, the privacy of experience, and other issues) that have been raised against the idea of composite minds. The result is an account of the metaphysics of composition and consciousness that can illuminate many different debates in philosophy of mind, concerning split brains, collective intentionality, and the combination problem, among others. (shrink)

I discuss the apparent discrepancy between the qualitative diversity of consciousness and the relative qualitative homogeneity of the brain's basic constituents, a discrepancy that has been raised as a problem for identity theorists by Maxwell and Lockwood (as one element of the ‘grain problem’), and more recently as a problem for panpsychists (under the heading of ‘the palette problem’). The challenge posed to panpsychists by this discrepancy is to make sense of how a relatively small ‘palette’ of basic qualities could (...) give rise to the bewildering diversity of qualities we, and presumably other creatures, experience. I argue that panpsychists can meet this challenge, though it requires taking contentious stands on certain phenomenological questions, in particular on whether any familiar qualities are actual examples of ‘phenomenal blending’, and whether any other familiar qualities have a positive ‘phenomenologically simple character’. Moreover, it requires accepting an eventual theory most elements of which are in a certain explicable sense unimaginable, though not for that reason inconceivable. Nevertheless, I conclude that there are no conclusive reasons to reject such a theory, and so philosophers whose prior commitments motivate them to adopt it can do so without major theoretical cost. (shrink)

Any panpsychism building complex consciousness out of basic atoms of consciousness needs a theory of ‘mental chemistry’ explaining how this building works. This paper argues that split-brain patients show actual mental chemistry or at least give reasons for thinking it possible. The paper next develops constraints on theories of mental chemistry. It then puts forward models satisfying these constraints. The paper understands mental chemistry as a transformation consistent with conservation of consciousness rather than an aggregation perhaps followed by the creation (...) of something in addition. The paper suggests that this kind of mental chemistry alone yields a workable panpsychism. (shrink)