In these combined lectures, James examines mysticism, often dismissed or used as a derogatory term in scientific circles. However, James asserts that religious experiences find their root in mysticism and advocates once more for an open mind. He invites his listeners to examine two critical questions: “What does the expression ‘mystical states of consciousness’ mean? How do we part off mystical states from other states?” (379). Another term for mysticism is “cosmic consciousness.” This term, coined by Canadian psychiatrist Dr. R. M. Bucke, suggests that mystical experiences cause the individual to tap into a larger realm of understanding.

James proposes that, like saintliness and conversion, mysticism is best understood through its characteristics. The psychologist identifies four qualities of mysticism. The first, ineffability, relates to the struggle many individuals have when trying to describe their experiences. Often, they argue that their religious experiences cannot be put into words. This means that religious revelations cannot be transferred from one individual to another; instead, they must be experienced individually. The second is noetic quality: People who undergo mystical experiences feel that they have been presented with great truth and knowledge. The third quality is transiency: Mystical experiences typically do not last more than half an hour, and in rare cases, they may last an hour or two.