English polymath Herbert Spencer worked as a sociologist, anthropological, biologist, psychologist, and philosopher. The phrase "survival of the fittest" was first used by Spencer in Principles of Biology (1864), following his reading of Charles Darwin's 1859 book On the Origin of Species. Although the name primarily denotes natural selection, Spencer also embraced Lamarckism since he believed that evolution extends into the fields of sociology and ethics. Spencer created a comprehensive theory of evolution that included the progressive development of biological systems, the physical environment, human thought, culture, and society. He made contributions to many different fields as a polymath, such as politics, economics, anthropology, ethics, literature, astronomy, biology, sociology, and psychology. He attained great power throughout his lifetime, mostly in academic English-speaking circles. Although Spencer was "the single most famous European intellectual in the closing decades of the nineteenth century," his impact began to wane after 1900. Talcott Parsons questioned, "Who now reads Spencer?" in 1937. Spencer, the son of William George Spencer (often referred to as George), was born in Derby, England, on April 27, 1820.