A small chance of disaster
European Review, vol. 21, no. S1, 2013, pp. S27—S31
Abstract
Expected utility theory tells us how we should make decisions under uncertainty: we should choose the option that leads to the greatest expectation of utility. This may, however, not be the option that is likely to produce the best result – that may be the wrong choice if it also creates a small chance of a great disaster. A small chance of disaster may be the most important consideration in decision making. Climate change creates a small chance of disaster, and some authors believe this to be the most important consideration in deciding our response to climate change. To know whether they are right, we need to make a moral judgement about just how bad the disaster would be.
Quotes from this work
If a catastrophe should really dominate our thinking, it will not be because of the people it kills. There will be other harms, of course. But the effect that seems the most potentially harmful is the huge number of people whose existence might be prevented by a catastrophe. If we become extinct within the next few thousand years, that will prevent the existence of tens of trillions of people, as a very conservative estimate. If those nonexistences are bad, then this is a consideration that might dominate our calculations of expected utility.