Critiques of humanitarianism have highlighted its conceptual ambiguity and its usefulness in justifying the exclusion, rather than inclusion, of refugees and asylum seekers. This facility for co-option can be traced to the tension between the opposing considerations of ‘costs to self’ versus ‘duty to others’ in liberal definitions of humanitarianism, and to the liberal binaries of reason versus emotion, moderation versus excess, and pragmatism versus idealism. Using discourse analysis, this paper explores how these binaries framed Australian political debates over asylum seeking, providing persuasive discursive resources for limiting humanitarian responsibilities for asylum seekers. The analysis demonstrates that the consideration of ‘costs to self’ is so flexible that these costs can be presented in such a way as to deny any humanitarian responsibility whatsoever. However, this paper also suggests that asylum seeker advocates’ arguments may be strengthened by drawing upon these same frameworks of reason, moderation and practicality.