Humanism is a secular religion thrown together from decaying scraps of Christian myth. In contrast, the Gaia hypothesis – the theory that the Earth is a self-regulating system whose behaviour resembles in some ways that of an organism – embodies the most rigorous scientific naturalism.
In James Lovelock’s model of Daisyworld, a planet containing only black and white daisies becomes one in which global temperature is self-regulating. Daisyworld is lit by a sun that grows hotter over time. White daisies reflect the sun’s heat, thereby cooling the surface of the planet, while black daisies absorb the heat, so warming the surface. Without any element of purpose, these daisies interact to cool their world despite the warming sun.
All that is required to bring a self-regulating biosphere into existence are mechanistic and stochastic processes, which can be modelled in a computer simulation. Joel de Rosnay explains:
The simulation … starts with a low temperature. The black daisies, which absorb the heat of the sun better, survive, develop and occupy a large area. As a result, the temperature of the soil increases, becoming more favourable to life. The black daisies reproduce at a high rate but cover too much area, and temperature increases above a critical point; the black daisies die off en masse. But the white ones adapt, develop, and colonize large areas, reflecting the heat and cooling the planet again. The temperature drops – too much. The white daisies die and the black ones return in profusion. After a certain number of fluctuations, a ‘mosaic’ of black and white areas begins to coexist and coevolve on the planet’s surface. Individual daisies are born and die, but the two populations, through successive heating and cooling, maintain an average temperature favourable to the life of both species, and this temperature fluctuates around an optimal balance. No one set the temperature, it simply emerged – the result of the daisies’ behaviour and their co-evolution.
Daisyworld arises from chance and necessity.
As the Daisyworld model shows, the Gaia hypothesis is consistent with the narrowest scientific orthodoxy. Even so, the hostility of scientific fundamentalists to it is well founded. At bottom the conflict between Gaia theory and current orthodoxy is not a scientific controversy. It is a collision of myths – one formed by Christianity, the other by a much older faith.
Gaia theory re-establishes the link between humans and the rest of nature which was affirmed in mankind’s primordial religion, animism. In monotheistic faiths God is the final guarantee of meaning in human life. For Gaia, human life has no more meaning than the life of slime mould.
Lovelock has written that Gaia was named after the ancient Greek goddess of the Earth at the suggestion of his friend the novelist William Golding. But the idea of Gaia is anticipated most clearly in a line from the Tao Te Ching, the oldest Taoist scripture. In ancient Chinese rituals, straw dogs were used as offerings to the gods. During the ritual they were treated with the utmost reverence. When it was over and they were no longer needed they were trampled on and tossed aside: ‘Heaven and earth are ruthless, and treat the myriad creatures as straw dogs.’ If humans disturb the balance of the Earth they will be trampled on and tossed aside. Critics of Gaia theory say they reject it because it is unscientific. The truth is that they fear and hate it because it means that humans can never be other than straw dogs.