Openness, confidence and trust in science and society

In this paper I discuss openness and its converse, closeness, in science and society. Openness is an aspiration which is achieved to varying extents in different situations and by different actors in human culture. I identify confidence (here used primarily in the sense self-confidence) and trust as essential conditions for openness to flourish, and integrity as an overarching quality which fosters openness, confidence and trust. The principal example here treated concerns the views and practice of the physicist Niels Bohr, in his science and in his advocacy of openness in the science-related matter of the international control of nuclear weapons.