“Bioconservatives” in the human enhancement debate endorse the conservative claim that we should reject the use of biotechnologies that enhance natural human capacities. However, they often ground their objections to enhancement with contestable claims about human nature that are also in tension with other common tenets of conservatism. We argue that bioconservatives could raise a more plausible objection to enhancement by invoking a strain of conservative thought developed by G.A. Cohen. Although Cohen’s conservatism is not sufficient to fully revive the (...) bioconservative objection, we argue that it can be supplemented by an account of reasonable partiality for humanity in a way that provides further support to the bioconservative position in a manner congruous with broader conservatism. We propose that the idea of partiality to humanity can buttress the bioconservative objection into its strongest possible form. However, we conclude by arguing that, even in this form, the objection cannot do all the work that bioconservatives expect of it. (shrink)