This theory has been around for a very, very long time. Anyone who thinks that the disappearance of oil will result in the death of humanity believes in three fundamentally incorrect assumptions: a) that the disappearance will happen overnight, b) that we don’t already know its happening and aren’t already doing something about it and c) that our economic system wont be able to adapt to it.
So to the first assumption; we know that oil is disappearing. We know that its becoming harder and harder to extract. Oil isn’t suddenly going to disappear overnight and we’re not all sudden going to go “but I am le tired” and suddenly let the world collapse around us.
Secondly, we’re already trying to stop it. The move to nuclear/renewable energy sources means a move away from other fossil fuels, and while nuclear power is non-renewable, its one hell of a lot more efficient than coal/oil/gas power plants. We’re also pushing out different kinds of transportation; public transport is becoming more awesome, we’re developing hybrid/electric/hydrogen cars, and we’re moving away from a dependence on fossil fuels.
And lastly, the idea that the economic system can’t adapt to the change. This leads directly on from the last idea; as oil becomes more and more expensive, people aren’t just going to roll over and die; they’re going to invest in different, more affordable areas. Those areas aren’t comparatively more affordable at the moment because the technology is still very underdeveloped and not ready for widespread economic production. As oil becomes more expensive, other areas, such as renewable energies, become more affordable, so more people invest. This, consequently, means that those technologies become more refined and, therefore, cheaper.
So we wont die. The more urgent the problem becomes, the more the price of oil increases and the more we invest in renewable energies, which means they get developed faster. The economic system can adapt and the end of the world is not nigh. At all.