There is already enough food to feed everyone in the world twice over
Really? That sounds like it should mean we have a massive waste problem. Enough food to feed (entire world's population + everyone who is not being fed now) is constantly being discarded. In that counterfactual world we really should be using food leftovers to produce fuel.
CarlShulman's mentioned food waste in developing nations, but there's non-negligible food waste elsewhere too. On a bigger scale, the EU's Common Agricultural Policy used to be infamous in the 70s and 80s for generating surplus beef & butter "mountains", although this is apparently a negligible problem now.
I'd be really interested to hear what the Less Wrong community thinks of this. Don't spoil it by reading the comments first.
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