James Lovelock is the originator of the Gaia Hypothesis (now Gaia Theory), on which he has written several books, including The Revenge of Gaia and The Vanishing Face of Gaia. He has been a fellow of the Royal Society since 1974, and he has been an honorary visiting fellow of Green College, University of Oxford since 1994. In 2003 he was made a Companion of Honour by her Majesty Queen Elizabeth II.