The Integrated Information Theory (IIT): Science, Pseudoscience, or Metaphysics?
The Integrated Information Theory of Consciousness (IIT) – regarded by many as one of the leading theories of consciousness in neuroscience – was recently accused, in an open letter signed by 124 researchers, of being pseudoscientific. In this talk, I argue that, while IIT is clearly not a purely scientific theory, its non-scientific (or non-empirical) part can be regarded as philosophical or metaphysical rather than pseudoscientific. Furthermore, other theories of consciousness (such as the Global Workspace Theory, IIT’s main rival) not only do, but indeed must, include such a component as well – no theory of consciousness can be purely empirical by virtue of the nature of its subject matter. One might still object to IIT that its philosophical component, in contrast to the philosophical components of other theories, is poorly grounded or especially implausible. I will focus on one especially controversial part of IIT, the Exclusion postulate (according to which conscious systems cannot overlap). I first offer a new way to ground this postulate (which is nevertheless in the spirit of its “official” defense). I then argue that other theories are also forced to take a stand on this postulate, and do not seem to have any firmer basis for either accepting or rejecting it.