Fred Pearce's attack on Vandana Shiva is an instructive example of how environmentalism without a recognition of the intrinsic value of nature is vulnerable to the self-serving ideology of utilitarian science and business, to the point where it can become the enemy of both nature and humanity alike.
Humanity has already appropriated nearly half of the planet's photosynthetic energy, and is conducting a mass extinction of perhaps half the world's other species within the next few decades. Pearce's and Norman Moss's "solutions" would only lock us more firmly into the global system that is driving this disastrous process.
As for using human overpopulation to justify further industrial intensification of agriculture, including bioengineering, do they really think this can continue forever? If not, the only question is not whether to try to reduce our numbers, but how: through relatively benign and voluntary measures or collapse?
In the not-so-long run, the only compassionate alternative is a gradual and humane downsizing to a truly sustainable steady-state of the kind envisaged by Shiva. "Sustainable growth" and "scientific management" are oxymoronic illusions that are costing us - and many, many others - the earth.