Your computer consumes barely no energy (in Joules). I'm not making a generalized abstract comparison, I'm making an energy consumption comparison. When you ea

Your computer consumes barely no energy (in Joules). I'm not making a generalized abstract comparison, I'm making an energy consumption comparison. When you eat a 10th of a cow per year (200g/day), you consume the same energy as one seat in a Paris-NYC flight, and the same energy as necessary to heat a house for a year, and the same energy as the Earth produces per year, per inhabitant. So, choose only one of those ;) It's not about saving tigers, kitties, noise or morality. It's that the Earth doesn't produce that much energy, so we're not in a stable situation on the long term. There are "footprint comparators" that you might have seen on the Internet: A European has a footprint of 2.5, which means it requires 2.5 Earths of wheat fields and uranium mines to feed, cloth and house everyone like a European. It takes 6 Earths to nurture someone like in the US. So we can only sustain this pace of spending resources as long as we keep others poor (aka as long as Middle East/China/Asia don't enter into a consumtpion society). That's where I claim: We may have to take part with our cars in the future and therefore we'd better build our cities so that we don't need to move around that ton of metal per person. The side effects of emitting CO2, nuclear waste, wars in the Middle East or costing an unsuspected cost through taxes are just different forms of the same constraint, which can be studied through energy consumption in Joules per inhabitant.