Bigelow's publicity for his vision of Japan extended to his teachings on Buddhism. He delivered the annual Ingersoll Lecture on the Immortality of Man at Harvard in 1908, which was published as a book in "Buddhism and Immortality". Bigelow used the scientific language of natural selection to explain spiritual evolution, as when an individual emerges from "unconditioned consciousness" and "moves up the scale of evolution guided by natural selection." Next, the individual moves to a level of celestial experience and finally is able to "return to the unconditioned consciousness from which all things emerge. In his view, familial ties were created by reincarnaton and what he called "thought transference."