The Gaia hypothesis is an ecological hypothesis proposing that the biosphere and the physical components of the Earth (atmosphere, cryosphere, hydrosphere and lithosphere) are closely integrated to form a complex interacting system that maintains the climatic and biogeochemical conditions on Earth in a preferred homeostasis. Originally proposed by James Lovelock as the earth feedback hypothesis, it was named—at the suggestion of his neighbor William Golding—the Gaia Hypothesis, after the Greek supreme goddess of Earth. The hypothesis is frequently described as viewing the Earth as a single organism. Lovelock and other supporters of the idea now regard it as a scientific theory, not merely a hypothesis, since they believe it has passed predictive tests.