That’s the title of the second chapter of his book One World: The Interaction of Science and Theology (2007, originally 1986). He argues that the triumphal view that science comprehends the universe with complete objectivity is false, just as the postmodern critiques of science as a purely social phenomenon that depends only on the judgment of the scientific community (in other words, charging they make decisions without any reference to evidence) is false as well. He argues instead that factual information interacts with scientific judgment to try to get closer and closer to describing the universe as it actually exists. I found his principles of science to be well-explained, based on the idea of critical realism, which balances the confidence that there is a reality to know with the caution that there is a human element in the process of knowing.
First, it has to recognize that at any particular moment verisimilitude [or the probability of being true] is all that can be claimed as science’s achievement — an adequate account of a circumscribed physical regime, a map good enough for some, but not for all, purposes….
Second, our everyday notions of objectivity may prove insufficient as we move into regimes ever more remote from familiar experience. [Here he gives the example of Heisenberg’s uncertainty principle in quantum theory, which states that we can’t know both the location and the momentum of an electron. Electrons are still real, though.]…
Third, a critical realism is not blind to the role of judgment in the pursuit of science….
We are to take what science tells us with great seriousness, but we are not to assign it an absolute superiority over other forms of knowledge so that they are neglected, relegated to the status of mere opinion. Our discussion has taken science off the pedestal of rational invulnerability and placed it in the arena of human discourse. (quotes taken from pages 28-31)
Polkinghorne is an Anglican priest (I don’t know which theological tradition of Anglicanism he belongs to) and had been a mathematical physics professor. I appreciate his approach because it takes science and reason seriously without indulging in the overconfidence or arrogance that has sometimes characterized scientists or defenders of scientific theories. At the same time, it avoids the postmodernist critique that we can ultimately know nothing.