Book excerpt: In the present study the author, director of mission studies and interreligious dialogue, Saint Paul University, Ottawa, Canada, proposes a dialogue between human sciences and missiology. Thanks to a path opened by the French philosopher Michel Foucault, Mooren analyses the pastoralized Western subject; the birth of the human sciences; how their constitution allows for a new vision of institutions like the Propaganda Fidei as well as of the Catholic China mission of the XVII/XVIII centuries. Throughout all this Mooren tackles that one question: why become a Christian at all?