On the need for real dialogue: What's wrong with monological contractualism?

According to T.M. Scanlon, the core idea of contractualism consists in the claim that what we are morally required to do is conceptually grounded in the value of living in “relations of mutual recognition” with others. Specifically, Scanlon's contractualist idea of “living in relations of mutual recognition with others” requires that one act only in ways that cannot be reasonably rejected by all of those affected, according to the results of a hypothetical reflection conducted within one's own mind. I claim, however, that Scanlon is mistaken to rely on a single individual's hypothetical reflection (monological reflection) to determine what no one affected could reasonably reject. Instead, following Jürgen Habermas, I claim that we must engage in actual dialogue with all who stand to be affected, in order to live in relations of mutual recognition with others.