Mental Medicine by Warren Felt Evans: The Forgotten Classic of New Thought

Warren Felt Evans’s Mental Medicine: A Theoretical and Practical Treatise on Medical Psychology (1873) is one of the most significant yet least remembered works of the early New Thought movement. Published at a moment when American metaphysical thought was crystallizing into a distinct spiritual and therapeutic tradition, the book offered a systematic argument for the power of the mind over the body, drawing on ideas from mesmerism, transcendentalism, and Christian Science. Although overshadowed by later New Thought classics, Evans’s treatise remains a cornerstone for understanding how mental healing evolved from fringe experimentation into a widespread cultural force. This article reconstructs the book’s historical context, its main arguments, and its place in the broader New Thought narrative, drawing on the original 1873 edition and its digital archives.

Historical Context

The mid-nineteenth century in America was a crucible of religious and philosophical innovation. The transcendentalist movement, led by Ralph Waldo Emerson and Henry David Thoreau, had popularized the idea of an immanent divine presence and the innate goodness of humanity. Simultaneously, the practice of mesmerism—a precursor to hypnotism—swept the nation, suggesting that the mind could exert profound physiological influence. Swedenborgianism, with its emphasis on spiritual correspondence and inner illumination, also shaped the intellectual climate. Into this ferment stepped Phineas Parkhurst Quimby, a clockmaker and healer who developed a system of mental healing that he called “the Science of Health.” Quimby’s method involved talking with patients to uncover and correct their false beliefs, which he saw as the root cause of illness. Warren Felt Evans, a Swedenborgian minister and former patient of Quimby, absorbed these influences and synthesized them into a coherent philosophy, culminating in Mental Medicine.

Main Narrative

Warren Felt Evans was born in 1817 in Rockingham, Vermont, and was ordained as a Methodist Episcopal minister before converting to Swedenborgianism. His spiritual journey led him to explore the relationship between mind and body, and he became one of the earliest writers to articulate what would later be called New Thought. Mental Medicine was his major systematic work, published in Boston by Carter & Pettee in 1873, the same year that Mary Baker Eddy was gaining attention for her own system of Christian Science.

Publication History

Mental Medicine was first published in 1873 by Carter & Pettee of Boston, as a 216-page volume measuring 20 centimeters in height. The book went through at least three editions, with the third edition also appearing in 1873 according to the American Psychological Association’s record. The work is now in the public domain and has been digitized by several institutions, including the Internet Archive, Google Books, and the Wellcome Collection, which hosts a scan from the Francis A. Countway Library of Medicine at Harvard Medical School. The Wellcome Collection notes that the book is available online and can be used for any purpose without restriction under copyright law.

Author and Historical Setting

Evans’s background as a Swedenborgian minister gave Mental Medicine a distinctly theological flavor. He argued that disease was not a physical entity but a mental state—a false belief that could be corrected through spiritual understanding. His work stood at the crossroads of several movements: the transcendentalist belief in the soul’s power, the mesmerist evidence of mind-body interaction, and the Swedenborgian doctrine of correspondence between spiritual and natural realms. Evans was also influenced by his personal experience with Quimby’s healing method, which he had sought for his own ailments. This blend of influences made Mental Medicine a bridge between the earlier metaphysical traditions and the institutionalized New Thought of the late nineteenth century.

Main Arguments and Key Concepts

The central thesis of Mental Medicine is that the mind is the primary cause of both health and disease. Evans argued that “medical psychology”—the study of the mind’s influence on the body—should be the foundation of all healing. He rejected the purely materialist medicine of his day, insisting that many illnesses were rooted in mental and emotional states such as fear, grief, and anxiety. Evans proposed that a change in belief, brought about by spiritual insight and prayer, could produce physical healing. He also emphasized the role of the healer’s own mental state, anticipating later New Thought teachings on the power of positive affirmation. The book systematically laid out a theory of mental healing that was both practical and theoretical, offering case studies and philosophical arguments.

Reception and Influence

Upon its publication, Mental Medicine was part of a growing wave of literature on mental healing. It likely reached an audience of metaphysical seekers, former Quimby patients, and those dissatisfied with conventional medicine. While it did not achieve the massive sales of later New Thought bestsellers like Ralph Waldo Trine’s In Tune with the Infinite (1897), it was cited and referenced by later writers. Evans’s work influenced key figures such as Emma Curtis Hopkins, who is often called the “teacher of teachers” for her role in training the founders of Divine Science, Unity, and Christian Science offshoots. Hopkins studied under Evans and then developed her own more radical teaching. The book’s emphasis on the mental causation of disease and the healing power of right thinking became a foundational assumption of the New Thought movement.

Editions and Where to Read

There have been several editions of Mental Medicine. The first and third editions both appeared in 1873, and later reprints have been issued by various publishers, including a modern facsimile edition. The original text is freely available online: the Internet Archive hosts a scanned copy, Google Books provides a digital preview, and the Wellcome Collection offers a high-quality scan from the Harvard Medical Library. Researchers can also find the book in major academic libraries that hold collections on American religious history or the New Thought movement.

Why It Matters in New Thought History

Mental Medicine matters because it represents a critical turning point in the development of New Thought. It was one of the first works to systematically articulate the idea that the mind can heal the body, not merely as a suggestion or placebo, but as a spiritual law. Evans’s synthesis of Swedenborgianism, transcendentalism, and Quimby’s mental healing provided a framework that later New Thought teachers could build upon. Emma Curtis Hopkins, for instance, took Evans’s ideas and radicalized them, emphasizing the absolute power of God-Mind and the unreality of disease. Charles and Myrtle Fillmore, founders of Unity, were also influenced by this intellectual lineage. In addition, the book’s practical focus on healing techniques—such as affirmation and prayer—prefigured the positive thinking movement that would dominate American self-help culture in the twentieth century. Without Evans, the New Thought movement would have lacked a crucial link between its metaphysical roots and its later institutional forms.

Primary Sources

• Mental Medicine: A Theoretical and Practical Treatise on Medical Psychology by Warren Felt Evans (1873). The original edition, published by Carter & Pettee. Available at the Internet Archive and Google Books.
• Wellcome Collection scan of the same work, from the Francis A. Countway Library of Medicine, Harvard Medical School. This digitized copy is in the public domain.
• Evans’s other works, including The Divine Law of Cure (1884) and Soul and Body (1876), which expand on the themes of Mental Medicine.
• Phineas Quimby’s manuscripts (1860s), which document the healing philosophy that Evans and others adapted.
• Emma Curtis Hopkins’s writings (1880s–1890s), including her magazine Christian Science (later Hopkins’ Magazine), which show her debt to Evans.