The Gaia Hypothesis Science on a Pagan Planet

In The Gaia Hypothesis, professor of philosophy Michael Ruse analyses the reception of Lovelock's ideas and delves into the historical and philosophical precursors to the notion of Earth as a living planet. An intellectually rigorous if sometimes challenging book, it gives a very satisfying overview of why Lovelock got the reception he did and, for me, as the first book by Ruse I read, marks him as a notable writer to keep an eye on.

Ruse opens with an introduction to the conception and basic premise of the Gaia hypothesis and the cast of characters. Scientists initially did not take it seriously. When it became clear that Gaia was not going away, they rained down both scorn and well-deserved critique on it. The general public, on the other hand, lapped it up. People were losing their religion while a countercultural revolution was in full swing. "Earth as an organism was just the vision, just the metaphor, for which many individuals and groups were searching" (p. 37). Ruse sees a paradox here. How is it that scientists rejected a fellow scientist-inventor, while a progressive counterculture embraced the ideas of a man funded by the military and the industry?

To resolve this paradox, Ruse provides a historical analysis in chapters 3 to 6 that form the core of this book. It was also the section that I found challenging in places, but that will be because I have no background in classical philosophy and metaphysics. Given this, I am stepping onto some very thin ice here, and I apologise in advance to all philosophers reading this if I am about to butcher some of your favourite concepts. That said, here is my understanding of the relevant points being made.

Ruse starts with Plato and Aristotle and their ideas on the nature of reality. They introduced different forms of teleology, which is the explanation of phenomena by arguing why—for what purpose or to what end—things happen in the world, rather than explaining what is causing them. Furthermore, no distinction was made between body and soul. Next to the soul animating the body (hylomorphism), of relevance to the Gaia hypothesis is that this animatedness extended to all matter, something Ruse refers to as "world soul thinking" or hylozoism. This notion waxed and waned over the centuries and an important hallmark of the Scientific Revolution was a gradual banishing of final causes. We moved towards an understanding in terms of mechanical metaphors, reductionism, and of matter as inert and without purpose. In particular, Ruse details the rise of mechanistic thinking and the expulsion of final causes in the two disciplines relevant to Gaia: geology and evolutionary biology.

Nevertheless, Plato's philosophy and the notion of a world soul persisted. Ruse traces a line through the German Romantic movement and American transcendentalism to the 19th-century rise of organicism, a school of thought in biology that erupted from intellectual hotbeds such as the universities of Harvard and Chicago. As defined here by Ruse, it stands in contrast to mechanism and argues that whole entities such as organisms are emergent properties. In the wider world, meanwhile, hylozoism lived on in e.g. deep ecology, ecofeminism, anthroposophy, and New Age paganism.

An important piece in the puzzle is Lovelock himself. Ruse provides a piercing if fair character study in the last two chapters. He is fair by pointing out that Lovelock demonstrated "outstanding talents" (p. 179) and his work with NASA showed "he did not break with traditional science; he simply did it better than anyone else" (p. 180). Ruse judges him to be "basically a very conventional scientist [who] was rightly elected to the Royal Society" (p. 181). However, this is no hagiography. His points confirm my suspicions that, frankly, Lovelock increasingly became a crank later in life. His response to criticism was "partly petulant" (p. 147), his attitude one of "cocky self-assurance [and] hubris" (p. 187). He was proud to be an independent scientist who dared to think outside the box and he felt disdain for academic institutes and peer review. The bigger problem Ruse highlights is that "Lovelock was not a biologist, didn't think like one, and wasn't about to start now" (p. 155). Lacking knowledge of classic philosophy, he was ignorant of the history of banishing teleology from evolutionary biology. He was "not a deep thinker [but] a tinkerer, an inventor, an instrument maker—and such people do think teleologically" (p. 187). Straying far outside his area of expertise and possessed of both ignorance and innocence, he "clearly had no idea of what he was embarking upon" (p. 186).

And then there was the company that Lovelock kept, with Ruse focusing on two people. First, there was the Nobel Prize–winning author William Golding who suggested the term Gaia. He used to be deeply involved with anthroposophy and was thus receptive to Lovelock's idea of Earth as a living being. Ruse beautifully summarizes his contribution thus: "The idea was Lovelock's, but the facilitator was Golding" (p. 183). Second, there was Lynn Margulis, the headstrong scientist who finally had won acclaim with her hypothesis of endosymbiosis but then went off the rails by seeing symbiosis everywhere. Though she continued to support Lovelock's cause throughout her life, they only co-published an initial batch of papers after which they gradually drifted apart.

How does all of the above help resolve the paradox of how Gaia was received? In a nutshell, public reception was positive because Gaia resonated with the spirit of the times and Lovelock was affable in his interactions, resulting in little scrutiny of either him or his ideas. The scientific reception was more hostile for several reasons. Lovelock neither could nor wanted to rid his idea of its implicit teleology. Having given it a fair hearing, Gaia was found wanting as a useful hypothesis. Gaia also entered the room when science was beleaguered by forces within and without. Finally, the enthusiastic and uncritical public reception made scientists wary. To put it mildly, Gaia "obviously did and still does on balance appeal more to those challenging conventional norms" (p. 200). Ruse concludes that "despite general agreement that Gaia had pushed thinking in some important directions, by around 2000 the Gaia hypothesis [....] had lost momentum" (p. 220).

Ruse tries to put a brave face on it when finishing the book: "no more talk of failure. Lovelock and Margulis were big people with a big vision. Whether science likes it or not, the vision lives on" (p. 224). To me, that belies the critical and piercing analysis in this book. The Gaia Hypothesis provides tremendous context, and will primarly appeal to a more intellectual audience, given Ruse's interest in history and philosophy.