This paper responds to Gui and Nelson's separate comments on our paper ‘Fraternity’, which analysed sociality in markets as joint commitment to mutual assistance. We argue that our analysis is fundamentally different both from Nelson's analysis (a mixture of self-interested and intrinsic motivations) and from that provided by theories of warm glow or guilt aversion, as discussed by Gui. We agree with Gui that, in initiating and maintaining cooperative relationships, individuals sometimes incur personal costs to benefit others without any certainty of reciprocation, but we argue that the intentions underlying such actions are cooperative rather than self-sacrificing.