William James identified mystical experiences by their ineffability and noetic quality, a concept later modified by W. T. Stace. Today, psychedelic research uses scales based on James to show that drugs like psilocybin and LSD reliably induce intense mystical states. Whether these states are necessary for therapeutic benefits is debated. This review examines James's original account of the noetic quality, its measurement in current studies, and concerns that psychedelic science may be epistemologically biased against atheistic or physicalist views, or that it improperly injects religion into science.
Psychedelic drugs such as psilocybin are claimed to reliably trigger mystical experiences, a claim justified using the Mystical Experiences Questionnaire (MEQ), which was developed from W.T. Stace's philosophy of mysticism. Scholars of Christian mysticism argue that Stace's framework inadequately represents Western theistic traditions. Stace, following William James, emphasizes intense, unusual moments of mystical union or fusion with the absolute, reflecting non-Western traditions. Christian mysticism, however, centers on a sense of loving presence and intimate closeness with the divine, not absorption or fusion. Love of God, central to Christianity, is absent from Stace and the MEQ30. For Christianity, mysticism involves lifelong interpretation and transformation, not momentary experience.
Psychedelic drugs show promise for treating mental health conditions by disrupting prior patterns and increasing neurogenesis and neuroplasticity. The social context during and after psychedelic experiences causally impacts outcomes. Modern cultural contexts may thwart spiritual integration, but local support groups help, especially for those reflecting on spiritual or religious themes. Christian communities can provide both a local social context and a set of theological beliefs that support spiritual growth and psychedelic spiritual integration.