Sidgwick famously claimed that an argument in favour of utilitarianism might be provided by demonstrating that a set of defensible philosophical intuitions undergird it. This paper focuses on those philosophical intuitions. It aims to show which specific intuitions Sidgwick endorsed, and to shed light on their mutual connections. It argues against many rival interpretations that Sidgwick maintained that six philosophical intuitions constitute the selfevident grounds for utilitarianism, and that those intuitions appear to be specifications of a negative principle of universalization (according to which differential treatments must be based on reasonable grounds alone). In addition, this paper attempts to show how the intuitions function in t...