 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 book "Buddhism and Immortality" (1908).There Bigelow used the scientific language of nature selection to explain spiritual evolution as when an individual emerges from "unconditioned consciousness" and "moves up the scale of evolution guided by natural selection."