This book brings the tools and ideas of Anglo-American analytic philosophy to bear on how we think about issues of contemporary significance, in a way that is accessible to a broad audience. While acknowledging empirical findings within the social sciences, it takes on the prescriptive task of imagining a better world, in which being citizens in a democracy means actively engaging with others.  We cling to tribal affiliations which incline us to look inward and spurn those whom we deem to be "other." And we observe the mind-numbing, herd-like impact of social (and other) media on our capacity - and that of our children - to distinguish truth and good sense from falsehood and nonsense. Such problems demand our attention as  reasonable  persons who both  think for themselves, and  deliberate in good faith with others  with whom they may well disagree. The good news is that while reasonableness cannot be taken for granted, it can -indeed, it must - be nurtured and it  must  be taught. This book both articulates a conception of reasonableness and exemplifies a clear standard of reasonableness, with respect to the questions it raises and the author's responses to them.