In the context of a day of annual training, organized by Bishop Luc Ravel and for military chaplains, Msgr. Jean Laffitte, Secretary of the Pontifical Council for the Family, was invited on February 7, 2013 to give two lectures in Dourdan (France). In the introduction of his first talk, entitled “L’altérité: l’énigme de l’autre” (Otherness: the enigma of the other), he discussed the characteristics of ethical relativism and of individualism as impediments to discovering the other. Bishop Laffitte then developed the topic, speaking first about the question of man in relation and the asymmetry of interpersonal relationships; then, he spoke about filiation and paternity. His second lecture on the theme “Les altérités fondamentales du rapport homme femme” (The fundamental differences in the relationship between man and woman), he addressed issues of sexual complementarity, its negation, and society as the recognition of otherness.