Science Denialism, Public Reason, and Political Parties

In the last years, science denialism, intended as the refusal to accept well-established scientific theories, laws, consensus, facts, and evidence, seems to have increased and gained broader visibility within democratic societies. Such form of denialism has bearing on many politically relevant issues. To appreciate the point, it suffices to recall some of the topics which are in the political crosshairs of denialists: climate change, vaccination, alternative medicine, GMOs. In this paper, I attempt to investigate and understand how science denialism should be treated in public discourse, when it comes to the justification of political norms and laws. Drawing from the assumptions that science is valuable in determining beliefs that are epistemically warranted and that it is possible to distinguish science from pseudoscience in some relevant manner, my aim is to understand whether it is possible to grant a special status to scientific findings and evidence when it comes to political justification, in consideration of the complexities of expert knowledge for ordinary citizens. Firstly, I consider John Rawls’s idea of political liberalism. Despite explicitly assuming that public reasons must include methods and results from science, Rawls’s framework seems open to scientific evidence and reasoning in political justification only insofar as they are commonly accepted and considered uncontroversial. For this reason, I argue that Rawls’s ideal seems attractive only in democratic societies in which there is no polarization concerning scientific findings that are relevant for public decisions and, thus, is unfit in present circumstances. Secondly, I focus on Gerald Gaus’s conception of “open justification”, according to which a certain norm is publicly justified insofar as all members of the public hold an undefeated reason, in their respective set of belief, to support it. I contend that, given the counterfactual nature of open justification, Gaus’s model seems unsuited to preserve scientific claims. Indeed, laypeople may be entitled to their ignorance because of the complexity and inaccessibility of scientific evidence. I then proceed by analyzing the role of scientific evidence and arguments in public discourse from the perspective of the ethics of belief. I contend that, although such standpoint can successfully exclude denialist claims from political justification, the ideal of citizenship it defends is too demanding with respect to the knowledge ordinary citizens should be able to acquire and access. To solve this problem, I propose to shift the focus from ordinary citizens to political parties. Indeed, parties play a fundamental function in influencing and reinforcing beliefs and values of those citizens who identify with them. Moreover, given not only the evidence stating that political ideology is directly linked with the acceptance or rejection of beliefs on scientific matters relevant to politics, but also the capacity of political parties to access and assess scientific evidence, they should be held responsible for failing to counter erroneous statements and promote claims that are in contrast with science.