Aleister Crowley (1875–1947), an influential and controversial figure in the world of Western esotericism, was a prolific English writer, mystic, and ceremonial magician. Best known for his esoteric works and founding the religious philosophy of Thelema, Crowley's life and teachings have attracted both fervent admiration and criticism. Expanding his influence across various domains, he penned 'The Psychology of Hashish' amongst his eclectic array of literary outputs. This work offers an exploration of the effects of cannabis on the human mind, filtered through Crowley's unique perspective combining mysticism with keen psychological insights. Crowley's literary style often wove together his extensive knowledge of mysticism, magick, and the occult with his experiences in altered states of consciousness. His writing is characterized by the use of symbolism and the bold proclamation of his personal spiritual and philosophical convictions. In 'The Psychology of Hashish,' Crowley's narrative is both analytical and autobiographical, reflecting his broader body of work, which ranges from poetry and essays to instructional texts on magickal practices. As with many of his writings, this piece blends scholarly exposition with personal experimentation, inviting readers to examine the interplay between substance and spiritual experience through Crowley's unique lens. Whether being hailed as a prophet of a new age or denounced as a practitioner of the dark arts, Crowley's legacy endures as a seminal figure in modern esoteric thought and literature.