Recently I listened to an interesting dinner-table debate between my teenage children about an issue that, to my mind, clearly raised questions closely related to the theme of encounter of rationalities. In a conversation about indigenous Kenyan hairstyles, my son had wanted to know why the Maasai ‘made’ their women folk shave their heads bald while young men stylishly braided their hair into what has become a popular and fashionable African hairstyle, not for men, but for women. My daughter, who is quite a gifted debater, responded that it was just tradition, and tradition never answers to anyone's ‘why’ question, especially when the questioner is an insider who is expected to just practice the norm. My son, in obviously frustrated wonder, then sought to know whether they could ever answer the question if it were asked by an outsider (of the tradition) like himself, to which his sister responded: ‘what makes you ask? I guess every tradition sets its own ways.’ The boy: ‘why can't everyone be left free to do what they feel they like at different times, just like I dress differently for different occasions?’ The girl: ‘You see, you are always reading and shifting your dressing according to the norms you want to conform to. You may not be aware, but you change from one set of norms to another, one when you are at College, and the other when you come home, can't you see?’ The rest of us sat there, choking with the temptation to join in, and suffering the frustration of being denied the chance. I in particular struggled to stay neutral, but I succeeded not only by not joining in, but also by not revealing that I was working on this paper, all the while thinking to myself: ‘this is all about the encounter of rationalities, and the arguments’ turns, back and forth, are all about the relative rationality of ends’. In many respects, and to my amazement, my daughter and son got immersed in debating the merits of the idea of autonomous reason. My amazement was not only about the depth of the cosmopolitan multiculturalism that these teenagers revealed in their debate, it also was about the revealed transient nature of the communities from which people source the points of view on the basis of which they question the rationality of opposing points of view. The topic of encounter of rationalities seemed, at least in the context of this dinnertime debate by teenagers, to be such a natural occurrence to anyone who consciously moves between different social and cultural locations. In this paper, I apply and expand the theoretical concerns raised by the two young people to the assessment of Kant's culture-free moral principles against a communitarian view of the resources of reason.