Chiara Caporuscio

This special issue focuses on the Philosophy of Psychedelics by Chris Letheby in the form of a book symposium. Introduced by Matthew Johnson, Letheby presents the main claims of this book that explores the apparent conflict between psychedelic therapy and naturalism in a préci​s.​​ Seven contributions criticize, expand or comment on Letheby's arguments, focusing either on his proposed mechanism for psychedelic therapy or on the epistemic implications. The symposium concludes with Letheby’s replies to these commentaries.

Chris Letheby’s defence of psychedelic therapy hinges on the premise that psychedelic-facilitated insights about the self are in a better epistemic position than those about the external world. In this commentary, I argue that such a claim is not sufficiently defended. More precisely, I argue that one element is underexplored in Letheby’s otherwise compelling picture: namely, that unlike new beliefs about the external world, beliefs about oneself have the capacity to turn into self-fulfilling prophecies. Recognising the psychedelic experience and the subsequent integration process as opportunities not only to apprehend certain facts about the self but also to actively shape and redetermine those facts is key to understanding the epistemic differences between insights patients have about themselves and about the external world.

Introspection has traditionally been defined as a privileged way of obtaining beliefs about one’s occurrent mental states, and the idea that it is psychologically and epistemically different from non-introspective belief formation processes has been widely defended. At the same time, philosophers and cognitive scientists alike have pointed out the unreliability of introspective reports in consciousness research. In this paper, I will argue that this dissonance in the literature can be explained by differentiating between infallible and informative introspective beliefs. I will argue that the latter are formed similarly to beliefs about the external world, and are therefore susceptible to similar success and failure conditions. Understanding introspection as belief-like will help to locate possible sources of error in regular as well as in pathological cases, carrying relevant implications for the relationship between experience, belief, and delusion.

In his recent book Bad Beliefs and Why They Happen to Good People, Neil Levy argues that conspiracy theories result from the same rational processes that underlie epistemic success. While we think many of Levy’s points are valuable, like his criticism of the myth of individual cognition and his emphasis on the importance of one’s social epistemic environment, we believe that his account overlooks some important aspects. We argue that social deference is an active process, and as such can be helped or hindered by epistemic virtues and vices. With this in mind, holders of bad beliefs acquire more responsibility than is considered by Levy.