There is no adequate definition of 'fine-tuned for life'

The discovery that the universe is fine-tuned for life - a discovery to whi ch the phrase 'the anthropic principle' is often applied - has prompted muc h extra-cosmic speculation by philosophers, theologians, and theoretical ph ysicists. Such speculation is referred to as extra-cosmic because an infere nce is made to the existence either of one unobservable entity that is dist inct from the cosmos and any of its parts (God) or of many such entities (m ultiple universes). In this article a case is mounted for the sceptical pos ition that cosmic fine-tuning does not support an inference to anything ext ra-cosmic. To that end three definitions of 'fine-tuned for life' are propo sed: the 'slight difference' definition, the (unconditional) probability de finition, and John Leslie's conditional probability definition. These three definitions are the only ones suggested by the relevant literature on fine -tuning and the anthropic principle. Since on none of them do claims of fin e-tuning warrant an inference to something extracosmic, it is concluded tha t there is no definition of 'fine-tuned for life' serving this function.