According to what is known as the phenomenal concept strategy, the difficulties we have fitting consciousness into a scientific picture may owe to the peculiar nature of our concepts. Some philosophers point to the fact that when we try to convey the feel of our experiences, we employ context-dependent gestures and/or utterances indexed to perspectives unique to each person. However, an indexical sign like “this” can pick out its target in space and time without any knowledge of “what” that target is, as evidenced by a locution like “I have no clue what this is.” Enlarging this menu of referential options, I call on the ideas of C. S. Peirce to evince three ways signs can refer, namely, by convention, causal contact, and similarity. As I argue in my monograph, Consciousness and the Philosophy of Signs, Peirce’s sign theory offers a non-psychological analysis of similarity and similarity recognition. Since similarity is not reducible to proximity, I argue that a theory of reference that uses shared quality can bypass some of the implausible consequences that plague current indexical accounts.
My work in philosophy of mind is slowly changing how philosophers view pragmatism. Most philosophers know Peirce as the founder of American pragmatism, but few know that he also coined the term “qualia,” which is meant to capture the intrinsic feel of an experience. Since pragmatic verification and qualia are now seen as conflicting commitments, I try to understand how Peirce could (or thought he could) have it both ways. My attempt to figure this out has, over time, blossomed into a very active research program.
I am also interested in the epistemological service that similarity-based signs can render. Specifically, I study how diagrams allow us to verify whether the inferences we make are any good. I organized an international symposium on diagrams at the 2015 Congress of Logic, Methodology, and Philosophy of Science. If the qualitative nature of diagrams can serve as direct evidence for logical entailments, then this would make inferences answerable to some form of empiricism. I recently argued for this in an article in Synthese. Because diagrams can halt disagreements, I am also interested in knowing at what point it is okay for a rational agent to walk away from skeptical concerns. In pursuing that question, I have called on the notion of “real doubt”―a kind of doubt that is not actively sought and thus accompanied by a sense of surprise. My work on that topic has appeared in Philosophical Papers. I have articulated some of the foundationalist implications of my stance in Metaphilosophy and Logos & Episteme. The most thorough statement of my metaphysical outlook is an article titled “A Less Simplistic Metaphysics.”