James Lovelock’s vision of Earth as a living cybernetic system is popular again. The surprising new preacher of Gaia is Bruno Latour. He uses the concept to refer to a holistic understanding of Earth, in which mankind is situated as integral part. Gaia becomes the catalyst and fundament for his philosophical attempt to design a new believe-system in the time of ecological crisis. But the concept of Gaia is characterised by a tension between the idea of a powerful but indifferent nature and a grandiose vision of total control over it. This tension reveals itself to be deeply rooted in cybernetic thought. It is not only apparent in Lovelock’s own writing, but also in simulation programs based on the Gaia hypothesis such as the Daisyworld model and the computer game “SimEarth: The Living Planet” (1991). The article will distinguish Lovelock’s from Latour’s concept of Gaia and relate them to first- and second order cybernetics as well as to two different approaches to computer simulation: system dynamics and cellular automata.