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 persons who both and 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 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.