In discussions about the ethics of enhancement, it is often claimed that the concept of ‘human nature’ has no helpful role to play. There are two ideas behind this thought. The first is that nature, human nature included, is a mixed bag. Some parts of our nature are good for us and some are bad for us. The ‘mixed bag’ idea leads naturally to the second idea, namely that the fact that something is part of our nature is, by itself, normatively inert. The Inert View claims that nothing normative follows from the mere fact that some trait is a part of our nature. If the Inert View is correct, then appeals to the value or importance of human nature in debates about enhancement are indeed misplaced. We argue that the Inert View is wrong, and that a certain concept of human nature – which we refer to as human form – does have an important role to play in debates about enhancement.