This paper explores how students invoked different conceptions of "nature" in eight socio-scientific group discussions about human gene therapy. The paper illustrates and discusses how the students articulated nature and to what extent they elicited science factual content in the process. While the students in this study invoked nature at key places in a variety of dialectical contexts in the discussions, these invocations were often uncritical appeals and rarely involved science factual content. Even when an argument from nature was challenged, the author of that argument would often shift the sense of nature rather than elaborate upon the argumentation. It is argued that if students were properly introduced to the evaluative character of the term "nature" it would not just be conducive to the quality of their argumentation, but also invite them to foreground science factual content at key places in their discussion. (Contains 3 notes.)