Abstract
The Pastoral Constitution, Gaudium et Spes, is a key document for fundamental theology. In it, for the first time, the Church openly discusses the anthropological question as a specific theme. It explains what Christian anthropology is and in what way the mystery of Christ sheds light on the mystery of man. From the point of view of fundamental theology, the document shows how theological reason is closely related to anthropological meaning. It takes note of the potential mediatory role of anthropology in a dialogue between faith and reason in the modern world