ABSTRACT
Many environmental issues are difficult because they involve empirical uncertainty. We lack knowledge of the actual outcomes of our actions, so we need to rely on judgments about probability. For example, since we cannot know the actual outcome of global warming, we need to rely on judgments about the probability of various future scenarios. There are some well-known consequentialist solutions to this problem. One of the most popular solutions is that we ought to maximize expected overall value, in which the expected value of an action is the average value of the possible outcomes of the action, weighted by the probabilities of these outcomes. What has received much less attention in the debate about environmental ethics and consequentialism is the problem of evaluative uncertainty: What should you do when you are not sure about your value judgments? For instance, what should you do if you think that both human and animal lives are valuable but not sure how valuable humans are as compared to animals? What should you do if you take seriously the risk of human extinction, but are not sure how bad this would be? Some philosophers have argued that the problem of evaluative uncertainty can only be solved if the consequentialist theory is radically revised so that it takes into account the agent’s evidence for various evaluative hypotheses.
