The term ‘human nature’ can refer to different things in the world and fulfil different epistemic roles. Human nature can refer to a classificatory nature (classificatory criteria that determine the boundaries of, and membership in, a biological or social group called ‘human’), a descriptive nature (a bundle of properties describing the respective group’s life form), or an explanatory nature (a set of factors explaining that life form). This chapter will first introduce these three kinds of ‘human nature’, together with seven reasons why we disagree about human nature. In the main, this chapter focuses on the explanatory concept of human nature, which is related to one of the seven reasons for disagreement, namely, the scientific authority ...