A number of insights of general relevance and significance for theology can be culled from the history of quantum theory. The first is that there is no universal rationality. Aristotelian logic holds in the macroscopic world, but quantum logic in the quantum world. The second is that there is no universal epistemology either. Any attempt to know the quantum world with classical clarity is condemned to failure. That world can only be known in accordance with its Heisenbergian uncertainty. These insights certainly encourage theology to hold fast to what it has found to be to be the necessary character of its discourse about God.
The physical world has been found not to be merely mechanical in character, as many had thought following the deterministic discoveries of Newtonian physics. The world is something more subtle and more supple than a clockwork universe. The role of metascientific decision in interpreting quantum theory in terms of open process shows that we can take with due seriousness all that science has to say without being condemned to think of ourselves as automata or that God is confined to the role of an externally interfering Clockmaker. The Creator can be believed to be providentially active within the open grain of created nature. Science has not established the causal closure of the world on its reductionist terms alone.
If physics teaches us anything it is surely that reality is surprising, to a degree often beyond our power to anticipate without the actual nudge of nature. In consequence, the natural question for a scientist to ask about a proposition, within science and beyond it, is not 'Is it reasonable?', as if we thought we knew beforehand the shape that rationality had to take. No one in 1899 would have regarded wave/particle duality to be a rational possibility. Instead, the natural question for the scientist to ask is 'What makes you think that might be the case?', open to the unexpected but demanding evidential support for what is being alleged. I believe that theology can approach its truth-seeking task in exactly the same way.
Published July 2012
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John Polkinghorne, KBE, FRS, is past President and now Fellow of Queens' College, Cambridge. Formerly Professor of Mathematical Physics at Cambridge University, he then turned priest and became the author of many books on science and religion, including "Quantum Theory. A very short introduction" (Oxford 2002) and "Science and Religion in Quest of Truth" (London 2011). In 2002, he recieved the Templeton Prize and became founding president of the International Society for Science and Religion (ISSR). More info here.