Ratzinger defended and reaffirmed Catholic doctrine, including teaching on topics such as birth control , homosexuality and inter-religious dialogue. The theologian Leonardo Boff , for example, was suspended, while others such as Matthew Fox were censured. Other issues also prompted condemnations or revocations of rights to teach: for instance, some posthumous writings of Jesuit priest Anthony de Mello were the subject of a notification . Ratzinger and the congregation viewed many of them, particularly the later works, as having an element of religious indifferentism ( . , Christ was "one master alongside others"). In particular, Dominus Iesus , published by the congregation in the jubilee year 2000, reaffirmed many recently "unpopular" ideas, including the Catholic Church's position that "Salvation is found in no one else, for there is no other name under heaven given to men by which we must be saved." The document angered many Protestant churches by claiming that they are not actually churches, but "ecclesial communities". 
The study of UFOs has received little support in mainstream scientific literature. Official studies ended in the . in December 1969, following the statement by the government scientist Edward Condon that further study of UFOs could not be justified on grounds of scientific advancement.   The Condon Report and its conclusions were endorsed by the National Academy of Scientists, of which Condon was a member. On the other hand, a scientific review by the UFO subcommittee of the American Institute of Aeronautics and Astronautics (AIAA) disagreed with Condon's conclusion, noting that at least 30 percent of the cases studied remained unexplained and that scientific benefit might be gained by continued study.