Researcher ORCID Identifier

Graduation Year


Date of Submission


Document Type

Open Access Senior Thesis

Degree Name

Bachelor of Arts


Philosophy and Public Affairs

Reader 1

Amy Kind

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Psychedelics have the power to induce in us an altered state of consciousness—a psychological experience radically different from our normal waking state of consciousness. Notable differences include changes in one’s perception of time, their sense of self, and the meaning and significance they attribute to things in their life. Across a broad range of testimonies, many people have reported characteristics of their psychedelic experience that bear a close resemblance to metaphysical accounts of ultimate reality from various cultures and time periods. In this paper, I explore the question of whether one can acquire knowledge of ultimate reality through psychedelic experience. Using an application of Bertrand Russell’s knowledge by acquaintance argument, I demonstrate that one’s perceptual experience in the altered state of consciousness, in combination with post-experience reflection, provides justification for knowledge of ultimate reality.