Two failed marriages to physicians did little to restore her faith in conventional medicine. Her low opinion of the medical profession is expressed in The Secret Garden, in her unsympathetic portrayal of Colin’s uncle, Dr. Craven, who is unable to cure, or even correctly diagnose, his nephew’s largely psychosomatic illness and indeed secretly hopes for the boy’s death. It is Mary Lennox who brings about Colin’s cure by introducing him to the healing power of the secret garden.

In a 1909 New York Times interview Burnett described her belief in a divine energy that could be channeled by the human mind:

We are today mysteriously conscious of this strange magic in the air that we will call the beautiful thought. It has so revitalized and stirred our souls that there has been in its most recent evolution a magnetic force that seems to me must almost stir the dead in their graves (Gerzina, p. 259).

The Secret Garden depicts this “beautiful thought” at work in the cure of Colin Craven. Until he encounters his cousin Mary, Colin is a victim of the power of negative thinking. He has spent his whole life surrounded by people who resent his very existence, blaming him for his mother’s death in childbirth and expecting him to become a hunchback like his father. The pessimistic atmosphere around him provokes an imaginary illness so overwhelming that he is actually unable to walk. Colin’s recovery begins when his cousin refuses to accept his negative beliefs, introducing him to the magic of the secret garden and encouraging him to have faith that, like the flowers in the garden, he too can grow and flourish. Burnett is so determined to propagate her belief in the power of thought to change reality that at one point, near the end of the novel, she even interrupts the narrative to address young readers directly with her explanation of the relationship between mind and body:

One of the new things people began to find out in the last century was that thoughts—just mere thoughts—are as powerful as electric batteries—as good for one as sunlight is, or as bad for one as poison. To let a sad thought or a bad one get into your mind is as dangerous as letting a scarlet fever germ get into your body (p. 229).

For Burnett, the source of healing thought is a God who is always present in the world and cannot be defined by any one set of religious teachings. By the time she wrote The Secret Garden she had largely abandoned the Anglican Christianity in which she was raised. In addition to her interest in Christian Science, she had studied Hindu scripture and dabbled in theosophy, an occult philosophy drawn from both Eastern and Western traditions, first expounded by Madame Helene Blavatsky in The Secret Doctrine (1888) and extremely fashionable in the first decades of the twentieth century. Burnett’s diverse spiritual interests are reflected in The Secret Garden. Although Dickon Sowerby celebrates the power of the garden by singing the doxology, a Christian hymn of praise, the children also perform healing rituals inspired by Indian “fakirs and devotees” (p. 184), and Colin recites a mantra similar to those recorded by William James in his description of “the religion of healthy-mindedness” :

Every morning and evening and as often in the daytime as I can remember I am going to say, “Magic is in me! Magic is making me well! I am going to be as strong as Dickon, as strong as Dickon!” And you must all do it, too. That is my experiment (p. 185).

The “magic” that brings about Colin’s cure is not specifically linked to Christianity; indeed it has a very pagan association with the seasons and cycles of nature. The divinity in the garden is nurturant and creative, not a lawgiver but a “Joy Maker” (p. 212), having as its priestesses the novel’s two positive maternal figures, Colin’s dead mother, Lilias, and Dickon’s mother, Susan Sowerby. It was Lilias Craven who originally cultivated the secret garden, filling it with the roses and other flowers she loved. Her death in childbirth following a fall in the garden caused her distraught husband to lock up the place and bury the key. Yet, as Susan Sowerby assures Colin, the spirit of Lilias Craven continues to reside in the garden, overseeing her son’s cure: “Thy own mother’s in this ’ere very garden, I do believe. She couldna’ keep out of it” (p. 213). Sowerby herself does not appear in the novel until very near the end, but she is constantly helping the children from behind the scenes. In a letter to the English publisher of The Secret Garden, William Heinemann, Burnett describes Susan Sowerby as “a moorland cottage woman who is a sort of Madonna” and the novel’s “chief figure” (Gerzina, p. 262).