The title of this issue of Science in Context – “Believing Nature, Knowing God” – is intended to suggest the moral, emotional, and cognitive conditions in which the historical alliance of “nature” and “God” operated, and to make a more general point about knowing and believing. The production of scientific knowledge includes mechanisms for bringing about acceptance that such knowledge is true, and thus for generating a psychological state of belief. To claim to have knowledge of nature involves an attitude of belief in certain epistemic values, in the procedures associated with them, and in the results to which they lead. “Nature,” both as a totality to be known, and as the sum of the results of research directed towards it, turns out to be an object of belief.