Gaia: goddess and idea.

This paper introduces Gaia theory to the general reader. It provides the necessary background to follow the development of James Lovelock's thinking as he originated the Gaia theory by comparison of the atmospheres around Mars and other planets during his sojourn at NASA. Lynn Margulis' contributions to Gaia are also presented and the bases for her collaboration with Lovelock explored. In addition to descriptions of the discoveries stimulated by Gaia thinking, the paper indicates how Gaians have dealt with the controversies that have arisen over the theory. Finally, the paper touches on the broader aspects of the Gaia idea. Namely, its development into a spiritual elixir, and how it has been a launching platform for interdisciplinary thinking inside of and beyond the boundaries of the sciences.