ANTHROPIC PRINCIPLE

The anthropic principle is a contentious principle of reasoning and confirmation that aims at accounting for selection effects from our place as observers when we evaluate or use theories. It is often invoked in the context of testing cosmological theories. The anthropic principle states that the parameters of the universe must be such that life (or conscious life or observership) is possible. A strong version of the anthropic principle claims that the most likely theories should be those that are most favorable to the advent of life. This strong version is contentious, as it implies that the universe is somehow designed for life. A weaker version of the anthropic principle claims that theories that are incompatible with the advent of life should be discounted for being empirically inadequate. This weak version is not contentious, but it's critics argue that it is nothing more than a truism of confirmation.