Of course we need farming to be productive – 10 billion mouths to feed in a few decades’ time is a lot – but we need to acknowledge that enough’s enough. We already produce enough for 14 billion people – 40% more than we should ever need – and the continuing demand from on high to produce 50% more by 2050 is pure commercial scam, not designed to “feed the world” but to make rich people richer. Focus now should shift to quality and wellbeing – of human beings, domestic animals, and the biosphere; and from the ludicrous and futile attempt to gear agricultural strategy to the short-term vagaries of the market, to the long-term future. In short, we need agriculture that produces excellent food, and is just, and is kind to animals, wildlife, and the fabric of the Earth, and is also – the clichéd but accurate terms – sustainable and resilient. All this – especially sustainability and resilience – is the special concern of agroecology.

The secret is to treat each farm as an ecosystem, and to treat agriculture as a whole, worldwide, as a key component of the biosphere. In truth, agriculture will always compromise the pristine biosphere to some extent but the intrusion must be as non-destructive as possible and even positive. After all, farms can and do create niches that are extremely rich in species, which is not in itself the be-all and end-all of conservation but is certainly significant.

Sustainable does not mean that we should go on doing the precise things that we do now, for ever and ever. It does mean that we should retain the ability to continue farming of some kind for ever and ever, starting with the next million years. This is possible if all inputs are renewable and all deficits replaced.

Resilient means we must continue to farm productively even though conditions change – which they will, and especially the climate.

But how? Nature taken all in all does not provide a perfect model – for nature can be extremely destructive. But nature has been commendably productive, continuously, for nearly 4 billion years, though conditions have swung from pole-to-pole tropics to pole-to-pole ice. So how has this been achieved?

We can identify three main tricks. First, with a few conspicuous exceptions, natural ecosystems are extraordinarily diverse (and are always diverse when you take the microbes into account). The diversity makes it hard for pathogens to spread because all the potential hosts are different (and microbes to some extent gang up against intruders). Thus, the rust fungus can run riot in a monocultural field of wheat. But in the wild where all hosts are subtly different it must produce billions of spores just to ensure that a few take hold.

More subtly, the relationship between the different species is in part competitive but overall it is synergistic, and in particular is mutualistic: each individual, and each species, benefits in net from the presence of the others. Most obviously, plants are eaten by animals whose dung is broken down by microbes which thereby create fertilizer for the next generation of plants. Or again: it has been shown both in the laboratory and in various wild habitats that several or many species operating side by side can hunt more efficiently and generally make better use of whatever nutrients are on offer than one species on its own.

Thirdly, wild ecosystems are generally low-input. Certainly there are hot spots; places where nutrients converge to create hugely productive environments, like estuaries, where rivers carry all kinds of materials from the land and then are pulled up short by the rising tide; or fields and woods after herbivores have gathered to feed or reproduce. But most of nature is of low fertility by modern agricultural standards and although wild ecosystems receive a constant flow of inputs from other ecosystems (the oxygen we breathe is largely produced by ocean diatoms, often thousands of miles away) none of them, emphatically, make use of fossil fuels. The energy in nature comes mainly from sunshine (plus the radioactivity that heats the Earth, and gravity that drives the tides).

These three basic qualities also give rise to others. Thus, the synergy of natural ecosystems means they tend to be cyclic. There is very little waste – and whatever leaks from any one ecosystem commonly makes its way back by one route or another. What one creature excretes, another consumes. Barring the odd hurricane or tidal wave, or the stirring of hooves, nature does not cultivate – or at least, it does not dig or plough. Invertebrates constantly churn the soil, particularly earthworms, and mulch is added in the form of dead plants, but otherwise the soil is left undisturbed.

So how do these fundamental principles translate into farming?

Well, diversity leads us to the mixed farm; combinations of different crops and animals sharing the same space, with genetic variation within each breed or variety. In short: avoid monocultures and in particular, wherever possible, avoid clones. Synergy implies that the different enterprises on the farm should be integrated. On traditional mixed farms, for instance, whey from cheese-making is a valuable feed for pigs, and straw from cereals provides both bedding and feed and in either case it finishes up as manure to fertilize the fields. Mixed farms par excellence are still to be found in South-East Asia: arable and aquaculture combined in the paddy fields; horticulture on all the higher ground; water buffalo, pigs, chickens, ducks, and carp.

Minimization of inputs and particularly of oil-based fertilizers and pesticides leads us to embrace organic farming. Organic should at least be seen as the default position: what all farmers and growers should do as a matter of course unless there is a very good reason to do otherwise. That high-input farming is now considered “conventional” is weird.

Reduction of cultivation leads us to minimum tillage or “min-till”, or indeed zero tillage, achieved not with the aid of herbicides but wherever possible by the various guiles of organic farming, including permaculture.

All this has enormous economic, social, and hence political implications. For farms that are maximally mixed and integrated and basically organic are bound to be complex – they are designed to be. So the husbandry must be intricate – which means they must be skills-intensive: not armies of slaves or serfs to do the work of tractors, but a great many skilled, hands-on farmers and growers. Britain could probably do with eight or ten times as many farmers as it has now. When enterprises are complex and skills-intensive there is little or no advantage in scale-up, so the agroecological farms that the world really needs should in general be small to medium-sized (though there is plenty of scope for small units to form various kinds of cooperative).

Such farms – complex, maximally polycultural, low-input, integrated, organic or quasi-organic, skills-intensive, small to medium sized farms that imitate wild ecosystems – are the diametric opposite of what is required in a market-led economy designed to maximize and concentrate short-term wealth:  high-input, oil-based, minimum to zero labour monocultures on the largest possible scale.  But they are what we have to build if we are serious about the future. Agroecology is the modus operandi of Enlightened Agriculture and hence of the Agrarian Renaissance.