ABSTRACT
Since their introduction to mainstream culture and medicine in the middle of the 20th century, psychedelic substances have been investigated for their therapeutic potential. Research on psychedelic therapy, or the use of moderate-to-large doses of psychedelics in the context of therapy, indicates that psychedelics have great potential to treat disorders such as depression, addiction, and anxiety. But how does psychedelic therapy work? In this chapter, I develop an account of the psychological mechanism of psychedelic therapy. I argue that psychedelic therapy works by generating a distinctive type of transformative experience in subjects (Paul 2014), or what I call an affective shift. In an affective shift, a subject's affective attitudes change in a way that alleviates their psychological problem. I then compare this account with other proposed psychological mechanisms, arguing that an affective transformation is plausibly the key causal variable in psychedelic therapy.
