A lot of eco-thinking is based on the idea that there is a ‘balance of nature’. If only humanity could figure out how to play its part in that balance instead of jumping wildly on the far end of the scales, the argument goes, then we could assure our own future and that of our fellow organisms.

But is there really such a thing as a ‘balance of nature’? And if there isn’t, does that mean that anything goes as far as we humans are concerned, that we should consider ourselves a ‘God species’, to use Mark Lynas’s phrase, and not allow our horizons to be restricted by the irritating constraints of existing biology?

My answers to those two questions are ‘no’ and ‘no’, and here I’ll briefly attempt to explain why.

There seem to be three distinct levels at which the ‘balance of nature’ is usually invoked – the whole earth system, individual ecosystems and inter/intra-species relationships. At the whole earth system level, the key idea is James Lovelock’s famous ‘Gaia’ theory, which proposes that the Earth is a self-regulating or homeostatic system with a goal – the regulation of surface conditions so as always to be as favourable as possible for contemporary life (Lovelock The Revenge of Gaia, p.208). The problem is right there in that sentence. For it’s one thing to posit homeostasis, and quite another to posit goals. A thermostatically controlled heating system is self-regulating but, unlike its designer, it is not a conscious agent with specific ‘goals’, and there are any number of reasons why the switch may suddenly be flipped. So I’d argue that at the earth systems level forces may exist that tend to conserve various planetary conditions, but this implies no ultimate direction towards a balanced end-state. Lovelock frequently talks about Gaia in the third person as if she is a goal-oriented agent, but he also says that he finds it useful to think of the Earth only as being like an animal, that Gaia is mere metaphor (The Revenge of Gaia, p.20). I don’t think he can have it both ways. If Gaia is mere metaphor (and I can’t see any evidence to suggest otherwise) then the ‘balance of nature’ is at best contingent and provisional, not intrinsic. There are no goals, and no reason to suppose that something won’t come along to switch the celestial heating system on or off. If Gaia truly exists, she must be some kind of mad, amoral scientist, hurling endless germplasm into an indifferent world, throwing curveball after curveball at it (or, being English, perhaps I should say googly after googly), and giggling as she watches whether it can cope. On reflection, I reckon she’s probably a man.

At the ecosystem level, I think we tend to overestimate natural balance partly because our short lifespan makes us perceive stability where ultimately there is none, and partly because we humans have largely succeeded in extracting ourselves from specific actual ecosystems. If we go for a hike in the woods it’s easy to marvel at the natural balance of the biota surrounding us, but ‘natural balance’ may not be the best descriptor for the relationships between actual organisms fighting their numerous battles for position in the woodland, except as an ex post facto description of the outcome of those battles. Similar arguments apply to natural succession. It’s tempting, for example, to think that nitrogen-fixing pioneer species work collaboratively with successor species to enrich the overall environment (with alder playing John the Baptist to the oak tree’s Jesus, for example), but biological research suggest that the priority has more to do with the superior colonizing strategies of the pioneer plants than of any necessary relationship between the two (Begon et al, Ecology, p.481-2). And the boundaries of ecosystems are never rigid, always in flux, always exchanging energy or other inputs at the margins…

At the inter/intra-species level – well, after many years of Social Darwinism proclaiming the competitive struggle for existence, red in tooth and claw, that now all looks rather more like the self-image of an aggressively expanding colonial society than anything deeply grounded in empirical science. But by the same token the stories we now often like to tell ourselves of biological coexistence and cooperation may reveal more about our own modern preconceptions than anything about the world beyond our window (indeed, coexistence can result from what ecologists call the ‘ghost of competition past’ and even genuine symbiosis in nature often turns out to be at another organism’s expense, such as the conspiracy against giraffes worked by acacias and ants). All in all, I suspect that anybody choosing to pin their colours to a particular point on the continuum between savage competition and blissful harmony as a description of biological process is as right, and as wrong, as anybody choosing an entirely different point. Better, I think, not to choose a point at all.

So if there is no real ‘balance’ in nature, does that mean that we humans should feel free to mess with it however we please? I’d like to answer ‘no’, and here’s why. Environmental philosophers have long attempted to show that living things have ‘intrinsic value’ aside from the values that humans place upon them. I don’t think they’ve succeeded, which in some ways I find regrettable but in others a relief, since the biocentric nature ethics of somebody like Paul Taylor puts you in a serious quandary about whether it’s ethically acceptable to actually eat. To be honest, I’m no longer terribly interested in debating the finer philosophical points of such analyses, but I find the writings of Aldo Leopold (eg. ‘The land ethic’ in his book A Sand County Almanac) and his latter day interpreters like J. Baird Callicott (eg. Beyond The Land Ethic) instructive. I’d offer the following brief encapsulation of their arguments in layman’s language: the natural world is complex, humans don’t understand all that much about it, and we gain when we try as much as possible to empathise with and learn from others rather than subordinating them to ourselves (which needn’t imply that we can’t eat them). Or, as Callicott puts it, “A thing is right when it tends to disturb the biotic community only at normal spatial and temporal scales. It is wrong when it tends otherwise” (Beyond The Land Ethic, p.138).

So if as a farmer I grow cabbages, like all other organisms I inevitably intervene in the biotic community and try to turn some of its resources to my own ends. My activities will be of great interest to others in the biotic community, such as cabbage white butterflies, who will do likewise. I could ignore them, and eat whatever remains of my holey, caterpillar-shit encrusted cabbages. Or I could make further interventions in the biotic community: I could cover my cabbages with enviromesh in a (usually fruitless, in my experience) attempt to stop the butterflies entering; I could plant lovage and yarrow nearby to encourage parasitic wasps to come along and lay their eggs inside the caterpillars until they’re eaten from inside out by the wasp larvae; I could spray the cabbages with a Bacillus thuringiensis preparation, or with pyrethrum; or perhaps I could plant transgenic cabbages with Bt toxin engineered into the genome.

All of these strategies make a determinate intervention in nature, and all will have many biotic consequences cascading down the succeeding generations, but if there is no ‘natural balance’ to which any of them converges which of them should I adopt? Going back to the land ethic and Callicott’s summary of it, I feel most comfortable with the ones somewhere in the middle of the list – ones which I suspect also score on grounds of long-term human self-interest, though sadly not short-term profit. Those middle strategies also appeal to me because I think they probably strike more of a balance between my ends and those of other members of the biotic community. For if ultimately there is no balance in nature, perhaps there’s something to be said for finding a balance in ourselves.