The Magic of Thinking Big is part of the self-help genre that traces its origins to New Thought, a system of beliefs that became popular in America during the 1800s. New Thought holds that thoughts create reality, and that the way people think about themselves, good or bad, determines the outcomes in their lives.

As part of the can-do traditions forming at that time in American culture, New Thought drew some of its precepts from transcendentalism, a philosophy popularized by American essayist and philosopher Ralph Waldo Emerson and, to some degree, the Unitarian Church. They held that goodness and the spiritual were inherent in the physical world, not separate from it, that people become corrupted by their interactions with society, and that true independence of thought revives creative insight and returns individuals, thus revived, to a better sense of community.

In the middle 1800s, American clockmaker and mentalist Phineas Quimby taught an early version of what would become New Thought. One of his students was Mary Baker Eddy, who believed that illness was an illusion and that Jesus taught as much. She formed a breakaway Protestant church, Christian Science, whose congregations grew rapidly during the late 1800s and early-to-mid 1900s.