Can a marker approach exclude?

Abstract

If an organism displays enough of the right neural, cognitive, or behavioral “markers,” researchers can generally assume it’s phenomenally conscious. But what if it doesn’t? Recently, there has been substantial disagreement on this “exclusion question.” According to one view (what I call the “symmetry” view), organisms lacking markers probably aren’t conscious (Dennett in Soc Res 62:691–710, 1995; Tye in Tense bees and shellshocked crabs: Are animals conscious?, Oxford University Press, New York, 2016; Birch in Noûs 56:133–153, 2022; Veidt in Biol Theory 17:292–303, 2022). However, according to another (the “asymmetry” view), we cannot conclude anything about the presence or absence of consciousness in organisms lacking markers (Prinz Conscious Cogn 9:243–259, 2005; Schwitzgebel in Philos Topics 48:39–64, 2020; Andrews in The animal mind: an introduction to the philosophy of animal cognition, Routledge, New York, 2020, Andrews in Anim Sent 10.51291/2377-7478.1737. 2022, Andrews in Mind Lang 39:415–433, 2024). Here I argue that this disagreement partially reflects a deeper disagreement about how markers are identified; to this end, I point to three “paths” from specific ideas about marker identification (namely, theory-based, analogy-based, and function-based approaches) to one or the other view on exclusion. Equipped with the right auxiliary assumptions, theory- and analogy-based approaches can motivate the asymmetry view, whereas function-based approaches can motivate the symmetry view. However, this relation is not deterministic, as different auxiliary assumptions will lead to different views about exclusion. My distilled product is therefore a decision tree, which links views about marker identification to one or the other view on exclusion. I hope that this tree will serve as a means of identifying “fronts” where future debate on this question can be productively focused.