Testing For the Supernatural

Christian apologist Bill Pratt is confused.  That's not just my judgment - it's what he says himself, in an article called Can Science Test for the Supernatural?  The issue in his mind is whether science can test for "the supernatural".  Pratt's puzzlement is a somewhat sarcastic response to the apparent contradictory stances of various members of the scientific community regarding the limits of scientific inquiry.  His real goal is to show hypocrisy among skeptics.  He notes:

Those who hold a naturalistic worldview (the natural world is all that exists) seem to be divided on this subject.  Some naturalists deny that science can ever be used to test the existence of God and others affirm that science can test for the supernatural and that those tests have all turned out negative.  Still others, like evolutionary scientist Donald Prothero, appear to hold both views at the same time.  - Pratt

To be sure, there is a certain amount of disagreement among religionists as to whether science can say anything at all about supernatural claims.  But perhaps aside from a few accommodationists, not so much on the part of the scientific community.  You just have to understand what they are saying.  But in the interest of scoring a point for his side, Pratt seems to be deliberately obtuse in his analysis.

To begin with, look at the way he frames the dispute.  Scientists say we can't test for the existence of God, which is true.  At the same time, there have been numerous scientific tests for certain specific supernatural phenomena, which is also true.  But he calls both of these things tests for "the supernatural".  One is an existential claim, and the other is about observable effects on the physical world.  So he seems to be equating two very different things, and pointing out what he supposes is a contradiction.  But it's not a contradiction at all.  If by using the term "the supernatural" he means the ontological existence of souls or deities, it is true that science provides us no means of detecting them or disproving them.  On the other hand, if the term refers to observable effects that may be due to some supernatural phenomenon, then certainly we can use scientific means to verify whether those effects can be found or measured.  For instance, if one claims that he has had an out-of-body experience, and could see things that wouldn't be visible from the body, then we would expect him to be able to describe things he saw, and verify whether his description is consistent with the reality.  That's a legitimate test of some specific claim of supernatural phenomena.

As for the statements of Donald Prothero, Pratt gives us two different quotes from his book Evolution: What the Fossils Say and Why It Matters that he thinks are contradictory.  The first one is about forming scientific hypotheses.

Prothero first suggests that scientists “cannot consider supernatural events in their hypotheses.”  Why? Because “once you introduce the supernatural to a scientific hypothesis, there is no way to falsify or test it.” - Pratt (quoting Prothero)

But read the entire passage from Prothero for yourself.  It isn't about a prohibition on testing.  It says that methodical naturalism precludes making supernatural hypotheses because it would entail untestable consequences.  Any such hypothesis would always entail a variety of consequences, some of which my be testable, but others could never be tested scientifically.  That's what makes the hypothesis unfalsifiable. 

The second quote says that unscientific claims of supernatural phenomena have been extensively tested, and those tests have always failed.

But in the very next paragraph in his book, he completely reverses course.  Prothero explains, “In fact, there have been many scientific tests of supernatural and paranormal explanations of things, including parapsychology, ESP, divination, prophecy, and astrology.  All of these non-scientific ideas have been falsified when subjected to the scrutiny of scientific investigation. ... Every time the supernatural has been investigated by scientific methods, it has failed the test.” - Pratt (quoting Prothero)

The passage from Prothero's book is here.  Note that this is about testing some specific claims of observable effects, not about the full regimen of testing that would be involved in verifying an actual scientific hypothesis.

Pratt says that this leaves his head spinning. 

Huh??  Is your head spinning like mine?  Prothero first claims that science cannot test the supernatural and then he says that science has tested the supernatural.  Which is it?  It can’t be both. - Pratt

Prothero doesn't conflate supernatural phenomena with supernatural hypotheses.  He uses the phrase "the supernatural" to refer only to the latter.  He never said that no testing of claims about supernatural phenomena can be done, and he isn't saying anything contradictory.  There certainly are untestable consequences of supernatural hypotheses (particularly unobservable existential issues), but at the same time, there are many unscientific claims of supernatural events or phenomena that are (or should be) observable, and subject to testing.  Pratt either didn't read what Prothero actually said, or he didn't understand it, or he is deliberately conflating different concepts in a dishonest effort to make his point.  He even goes on to say that this "mistake" is commonplace among skeptics.  But the mistake is entirely on his part, whether or not it is deliberate.  Science can be used to test whatever has an observable effect on our world, regardless of whether it purports to be "the supernatural".

If Pratt has a problem with what he sees as contradictory or hypocritical stances on the part of skeptics, he doesn't seem to have any such problem with his fellow theists doing the same thing.  It is quite common for theists to shield their beliefs from any scientific examination by claiming that it is beyond the scope of science.  But then they waste no opportunity they find to make claims that science supports their religious beliefs about the existence of God.  Pratt himself says that the "big bang" is evidence for God as the creator, and that "fine tuning" is evidence for God as the designer of the universe.  (Both of these claims are highly dubious from a scientific perspective.)  And People like Joe Hinman claim that "the religious a priori" gives them justification for belief in God that is not subject to scientific scrutiny of any kind.  Yet at the same time, he is the author of a book that claims to provide scientific evidence that provides "warrant" for belief in God.  I guess he's just hedging his bets.  Go figure.

The bottom line is that religionists like Pratt, whether through ignorance or dishonesty, are spreading disinformation about the relationships between science and their religious claims.  It's not skeptics who need to decide whether science has anything to say about religious claims.  It's simple.  Whatever purports to affect the physical world in some observable way is subject to scientific scrutiny.  Existential claims about supernatural entities are a different matter.  And that's something that virtually all scientists agree about.  Now, if only Pratt would make an effort to understand what they are saying ...