If, in the course of a thousand or two thousand years, science arrives at the necessity of renewing its points of view, that will not mean that science is a liar. Science cannot lie, for it's always striving, according to the momentary state of knowledge, to deduce what is true. When it makes a mistake, it does so in good faith. It's Christianity that's the liar. It's in perpetual conflict with itself.

Table talk, 1941-1944 (ed. 1953)