I read an item or two from The Edge's World Question Center 2008 now and then, usually because someone else posted about some response. I then read a few others on the page. Some are useful, others, not so much. Today following Hanson's pointer to Sabbagh, I read on to Colin Tudge.

I have changed my mind about the omniscience and omnipotence of science. I now realize that science is strictly limited, and that it is extremely dangerous not to appreciate this. . .

In the matter of GMOs we are seeing the crude simplifications still in their uncorrected form. By genetic engineering it is possible (sometimes) to increase crop yield. Other things being equal, high yields are better than low yields. Ergo (the argument goes) GMOs must be good and anyone who says differently must be a fool (unable to understand the science) or wicked (some kind of elitist, trying to hold the peasants back).

But anyone who knows anything about farming in the real world (as opposed to the cosseted experimental fields of the English home counties and of California) knows that yield is by no means the be-all and end-all. Inter alia, high yields require high inputs of resources and capital — the very things that are often lacking. Yield typically matters far less than long-term security — acceptable yields in bad years rather than bumper yields in the best conditions. Security requires individual toughness and variety — neither of which necessarily correlate with super-crop status. In a time of climate change, resilience is obviously of paramount importance — but this is not, alas, obvious to the people who make policy. Bumper crops in good years cause glut — unless the market is regulated; and glut in the current economic climate (though not necessarily in the real world of the US and the EU) depresses prices and put farmers out of work.

Eventually the penny may drop — that the benison of the trial plot over a few years cannot necessarily be transferred to real farms in the world as a whole. But by that time the traditional crops that could have carried humanity through will be gone, and the people who know how to farm them will be living and dying in urban slums (which, says the UN, are now home to a billion people).

Behind all this nonsense and horror lies the simplistic belief, of a lot of scientists (though by no means all, to be fair) and politicians and captains of industry, that science understands all (ie is omniscient, or soon will be) and that its high technologies can dig us out of any hole we may dig ourselves into (ie is omnipotent).

Well, if he has changed his mind it wasn't recently since this is the same old wine he has been peddling for years. See Tudge Mudge for an example. He doesn't seem to have learned a thing since then much less changed his mind.

I know something about farming and can testify that he is full of manure. High yields do not require high inputs of resources and capital, they require skill. Management is the input of highest value.

One part of skilled management is knowing when and how to apply input and capital to get the highest benefit. One attribute of some GMOs is that they require less inputs and capital. Knowing that, a good manager may use them, even if they do not result in higher absolute yields. The GMOs posted about recently that make better use of nitrogen, reducing the amounts required for high yields, is an example.

It's important to grasp that we need to become very much more productive. Even if we weren't squandering crops on bio-fuels - creating hardship for some of the poorest among us - we expect population to continue rising for a few decades, adding another 3 billion people. Though fertility rates are dropping we live longer than in the past, and fertility rates are still above replacement levels in some of the poorest, most populous parts of the world. The notion that "traditional crops . . . could have carried humanity through" denies reality. They couldn't even have gotten us this far.

The claim that "a lot of scientists . . . [believe] that science understands all . . . and that its high technologies can dig us out of any hole we may dig ourselves into" has no basis in reality. It is more accurate to say that there is wide belief that science has a better chance of getting us through to the next screen than anti-science. It may not be enough but it is better than the alternatives.

Read that old post, Tudge Mudge, for a fuller discussion of Tudge's unchanging ideas.