As a work of speculative fiction, the title suggests that the narrative revolves around the possibility of life on Mars and the belief in a future existence in that distant planet. During the late 19th and early 20th centuries, there was a fascination with Mars, and the idea of extraterrestrial life was a popular theme in literature.L. P. Gratacap, the author, was a naturalist, geologist, and paleontologist who also dabbled in speculative fiction. The novel likely explores themes of science, spirituality, and the imagination prevalent in the early 20th century.If you are interested in early 20th-century speculative fiction and the fascination with Mars during that time, "The Certainty of a Future Life in Mars" may offer a unique perspective on the scientific and literary trends of the era.