A note on falsification By Edward Feser
- Antony Flew’s famous 1950 article “Theology and Falsification” posed what came to be known as the “falsificationist challenge” to theology. A claim is falsifiable when it is empirically testable -- that is to say, when it makes predictions about what will be observed under such-and-such circumstances such that, if the predictions don’t pan out, the claim is thereby shown to be false.
- As Popper himself emphasized, it is simply an error to suppose that all rationally justifiable claims have to be empirically falsifiable. Popper intended falsificationism merely as a theory about what makes a claim scientific, and not every rationally acceptable claim is or ought to be a scientific claim... For example, the thesis of falsificationism itself is, as Popper realized, not empirically falsifiable.... Claims of mathematics and logic are like this too. ...
- Now, the fundamental claims and arguments of theology -- for example, the most important arguments for the existence and attributes of God (such as Aquinas’s arguments, or Leibniz’s arguments) -- are a species of metaphysical claim. Hence it is simply a category mistake to demand of them, as Flew did, that they be empirically falsifiable.
- There is also the problem that, as philosophers of science had already begun to see at the time Flew wrote, it turns out that even scientific claims are not as crisply falsifiable as Popper initially thought. Indeed, the problem was known even before Popper’s time, and famously raised by Pierre Duhem. A scientific theory is always tested in conjunction with various assumptions about background conditions obtaining at the time an experiment is performed, assumptions about the experimental set-up itself, and auxiliary scientific hypotheses about the phenomena being studied.
- the characteristically Aristotelian argument for God’s existence -- the argument from change to the existence of an unchanging changer of things (or, more precisely, of a purely actual actualizer of things) is grounded in the theory of actuality and potentiality, and thus in what natural science itself must take for granted
