In which of Lowell's influential books, published in 1908, did he present a philosophical argument supporting extant Martian life?

Answer

Mars as the Abode of Life

The book titled *Mars as the Abode of Life*, published in 1908, focused on the philosophical argument for the existence of extant Martian life.

In which of Lowell's influential books, published in 1908, did he present a philosophical argument supporting extant Martian life?
MarsscientistAstronomerobservationplanet