A charge often levied against organic agriculture is that it is more philosophy than science. There's some truth to this indictment, if that it what it is, though why organic farmers should feel defensive about it is itself a mystery, a relic, perhaps, of our fetishism of science as the only credible tool with which to approach nature. ... The peasant rice farmer who introduces ducks and fish to his paddy may not understand all the symbiotic relationships he's put in play--that the ducks and fishes are feeding nitrogen to the rice and at the same time eating the pests. But the high yields of food from this ingenious polyculture are his to harvest even so.