According to John Rawls, the methods and conclusions of science—when these are non-controversial—constitute public reasons. However, several objections have been raised against this view. This paper focuses on two objections. On the one hand, the associational objection states that scientific reasons are the reasons of the scientific community, and thus paradigmatically non-public in the Rawlsian sense. On the other hand, the controversiality objection states that the non-controversiality requirement rules out their public character when scientific postulates are resisted by a significant (...) portion of the citizenry. The paper replies that both objections miss their mark. To the associational objection, it replies that the relevant test for a reason to be public is whether the reasons have been construed under the rules and constrains of a public frame of thought. Insofar as scientific methods and conclusions correspond to the principles of reasoning and rules of evidence that liberals understand as public, their associational origin is secondary. To the controversiality objection, it replies that the standard for a scientific argument to be regarded as non-controversial should refer to its degree of intra-scientific consensus, since ordinary citizens accept or reject scientific pronouncements conditioned to their particular comprehensive views. Nonetheless, a wide extra-scientific agreement on the epistemic virtues of the scientific method will be needed. The paper concludes that there is a good case to think about scientific reasons as public to the extent that scientific reasoning is a mode of inquiry that mirrors a central aspiration of Rawlsian political liberalism: having a public way of thought and an impersonal standpoint to adjudicate between competing claims. (shrink)