Psychological unity of one form or another is often claimed to be essential to our ordinary self-understanding and to our relationships, social practices, political philosophies, legal institutions—to human life as we know it. At the same time, it is also often said that the sciences of the mind/brain undercut all our claims to being unified. One major strand of my work investigates claims of the former sort, that is, whether and in what sense we assume we are unified. A second strand investigates claims of the latter sort, that is, whether and in what sense science reveals us to be disunified.
Some current and recent projects
Consciousness after split-brain surgery: The recent challenge to the classical picture
[with Tim Bayne]
In a recent series of experiments, Pinto and colleagues found that the split-brain patient D.D.C. was able to respond accurately to stimuli in either visual field, whether using his right hand, his left hand, or verbally. Pinto and colleagues argue that this demonstrates that a split-brain patient remains a unitary agent and thus continues to possess a unified consciousness. This paper provides a critical evaluation of that claim. First, we argue that two conceptions of the unity of consciousness need to be distinguished: an agency-based conception and an experience-based conception. Second, we argue that it is an open question whether the data presented by Pinto and colleagues is best understood in terms of the unity of agency. Whether that interpretation is correct depends not only on the mechanisms that produce split-brain behaviour, but also on what is involved in being a single agent. Third, we argue that even if the behavioral data indicated that D.D.C has a unified consciousness in the agency-based sense of the term, it is difficult to reconcile them with the claim that his consciousness is fully unified in the experience-based sense.
Plurals and plural identities
The paper introduces a population of human beings called plurals. A plural has a plural identity, in some sense identifying himself as one of multiple persons sharing his body, or brain, or mind. Many plurals request some sort of respect for their plural identities and even recognition as plural persons, or plural recognition. Plurals raise a number of interesting philosophical questions about the nature of identities, the nature and basis of respect for unfamiliar identities, and the relationship between personhood and recognition.
The avowal account of self-deception
An adequate account of self-deception must accommodate both the psychic tension characterizing self-deception and the fact that this tension doesn’t manifest in the self-deceived agent’s avowals. I have two papers on this view of self-deception. The first defends a version of the view according to which, at least in some "deep tension" cases, the agent who is self-deceived that p believes that ~p and yet is committed to believing that p. This makes at least this sort of self-deception intentional and motivated by a desire to believe that p other than for the sake of believing that the proposition that p is true. The second paper argues that if some cases of self-deception are like this, and if the avowal view offers the best account of them, then the agent's biased treatment of the evidence bearing on the proposition that p cannot be to produce the state of self-deception, contrary to what is standardly believed.