Public reason as a political ideal aims to reconcile reasonable disagreement; however, is public reason itself the object of reasonable disagreement? Jonathan Quong, David Estlund, Andrew Lister, and some other philosophers maintain that public reason is beyond reasonable disagreement. I argue this view is untenable. In addition, I consider briefly whether or not two main versions of the public reason principle, namely, the consensus version and the convergence version, need to satisfy their own requirements. My discussion has several important implications for the debate on public reason.