Sunday, November 25, 2007


Science and faith

In Saturday’s New York Times, Paul Davies, of Arizona State University, has an op-ed piece called “Taking Science on Faith”. From the blurb in the RSS feed I was prepared to flame against the stupidity of it, but on reading it as a whole I find that it doesn’t bother me as much as I expected it to. In fact, it has some things in common with this post, which I wrote a couple of summers ago.

Professor Davies’s premise is this:

Science, we are repeatedly told, is the most reliable form of knowledge about the world because it is based on testable hypotheses. Religion, by contrast, is based on faith. The term “doubting Thomas” well illustrates the difference. In science, a healthy skepticism is a professional necessity, whereas in religion, having belief without evidence is regarded as a virtue.

The problem with this neat separation into “non-overlapping magisteria,” as Stephen Jay Gould described science and religion, is that science has its own faith-based belief system. All science proceeds on the assumption that nature is ordered in a rational and intelligible way. You couldn’t be a scientist if you thought the universe was a meaningless jumble of odds and ends haphazardly juxtaposed. When physicists probe to a deeper level of subatomic structure, or astronomers extend the reach of their instruments, they expect to encounter additional elegant mathematical order. And so far this faith has been justified.

And yes, that’s true: we, as scientists, depend on repeatability and consistency. We take as an axiom — I won’t say it’s on faith — that things behave in consistent ways, ways that are predictable when you understand the mechanisms. We “know” that electrons won’t suddenly switch to positive charges, that water won’t start freezing at 30 degrees celsius, that gravity won’t stop all of a sudden — and, as Dr Davies uses in his column, “that we won’t wake up tomorrow to find heat flowing from cold to hot, or the speed of light changing by the hour.”

The concept that those “rules” might change is something we call “magic”, or, in different contexts “sorcery” or “divine intervention”. Consider a boy who might slip at the edge of a cliff, falling to certain death below. We know he’ll fall to the bottom, and we know he’ll die when he hits the ground. But suppose he should stop part-way down and float back safely to the top, while we all watched. There was a time when we’d select someone in the community who we didn’t like, someone a bit strange, and attribute it to her, calling her a witch. Or — and we’d certainly still do this today — we’d say that God saved the boy.

The difference here is that the scientists among us would say, “WTF?”, and would start trying to figure out what really happened, operating under the assumption that there was some cause that’s consistent with the way the universe works. If the universe does not, in fact, work that way, well, they’d be stymied. But so far, as Dr Davies points out, we have found no such inconsistencies — that which we observe, at least those things with credible reports, continue to follow the rules.

And that’s where Dr Davies strays into silliness:

When I was a student, the laws of physics were regarded as completely off limits. The job of the scientist, we were told, is to discover the laws and apply them, not inquire into their provenance. The laws were treated as “given” — imprinted on the universe like a maker’s mark at the moment of cosmic birth — and fixed forevermore.
No, they weren’t “off limits”. Indeed, if someone could find credible evidence that the laws of physics were changing — evidence that could be clearly shown to others — the discoverer would kick off a chain reaction of experimentation and would likely win a Nobel prize. That we’re advised not to try isn’t because the scientific community is “faithful” to some set of “beliefs”, but because our observations have shown, over a long stretch of time, that the search is a waste of time. And so if you want to waste your time, go ahead... but don’t expect to be taken seriously.

And should that “waste of time” pan out, should you discover the undiscoverable, well, yes, your work will be looked at with extreme skepticism. But it will be looked at, and if it holds up it might well change how we think about the world. Science has done that before, certainly, and it will do it again if it’s warranted.

It’s simply disingenuous to say that beliefs anchored in folk tales and “beliefs” anchored in centuries of careful observation are related in any real sense; indeed, it’s disingenuous to call the latter “beliefs”. We don’t understand why the laws of physics are as they are, no. We don’t know the mechanism that set them in motion, and as I say in my post, linked above, I don’t think we can know. But when the sun goes dark in the middle of the day, we now understand that it’s been occulted by the moon’s disc, and we don’t make up stories about dragons having lunch or God being angry.

And just as Christians claim that the world depends utterly on God for its existence, while the converse is not the case, so physicists declare a similar asymmetry: the universe is governed by eternal laws (or meta-laws), but the laws are completely impervious to what happens in the universe.

It seems to me there is no hope of ever explaining why the physical universe is as it is so long as we are fixated on immutable laws or meta-laws that exist reasonlessly or are imposed by divine providence. The alternative is to regard the laws of physics and the universe they govern as part and parcel of a unitary system, and to be incorporated together within a common explanatory scheme.

In other words, the laws should have an explanation from within the universe and not involve appealing to an external agency. The specifics of that explanation are a matter for future research. But until science comes up with a testable theory of the laws of the universe, its claim to be free of faith is manifestly bogus.

It’s Dr Davies’s argument that’s “manifestly bogus.” Observing a consistent, predictable, repeatable set of mechanisms and postulating that because we haven’t seen them change they likely will not change... is not “faith”. Believing that something will behave a certain way because we’ve seen it do so over and over again for centuries... is not “faith”.

It’s reality, for any sensible definition of “reality”. Could we find, some day, that we’ve been wrong about some of this? Of course. Might some of these “laws” one day change without warning nor explanation? They certainly might. But they haven’t yet, and until they do we’ll continue working under the assumption that they won’t.

Faith makes up answers and tells us to believe them because someone said so. Science postulates answers consistent with observation, and continually tests those postulates and adjusts them as new observation pushes and pulls at our understanding.

They’re not the same thing, and to say they are is what’s “manifestly bogus.”


Brian York said...

Just to throw a bit more fuel on the fire, there are indeed people looking for possible changes in physical laws (specifically, for possible changes in the fundamental constants, but that works out to a very similar thing). In particular, there's a group of astronomers headed by Michael Murphy who have done some excellent work in this area. This is a good recent summary.

While this work is not free from controversy (and, having talked with Dr. Murphy on the subject I'm sure that he would agree that the evidence is not conclusive yet, but it is interesting, and it shows that not only do scientists actually look for possible variations, but that they are also open to the possibility of someone finding such variations, assuming of course that any such discovery can make it through peer review.

-Brian York

Maggie said...

Oh, gosh, I first saw this article yesterday and posted to my blog about it ... I didn't realize you'd posted on it! I think the guy is making the mistake of trying to use science to fill the hole that religion has left behind. Why is he expecting science to answer religious questions? The article really annoyed me. I got the impression he was just trying to promote his book, and accusing science of being founded on "faith" was a way that would appeal to the religious. Maybe it's just to get them to read the book and it's actually very scientific, but I doubt it based on his silly argument style. I got the impression that this guy is a real boor at cocktail parties... harassing his "physicist colleagues" with his dumb questions. I think he should get a degree in physics and answer them himself. Or maybe if he were able to get a degree in physics, he'd realize he's barking up the wrong tree and switch to theology.

Barry Leiba said...

Maggie, yes, I read your blog entry about it last evening.

I don't think he's trying to "fill the hole". I think he's trying to say that science is built on faith too, so religious people don't need to be afraid of it. That's why I said that it doesn't bother me as much as I thought it would -- I think he's using the silly "faith" argument to popularize physics, and make it less threatening to people who find "faith" to be a comfort.

I think it's a bad mechanism for that, though. I think there are a lot of "people of faith" who do not need nor want faith in their science. And I think the people who are suspicious of anything that "rejects faith" will not be mollified by his attempt.

And, um... he does have a degree in physics, a PhD from Universty College, London (see his c.v.).

Maggie said...

Agh, he does! I'm going to stop trying to guess his motivations, then, and just say I don't agree with his logic or conclusions. The "we are repeatedly told" (by whom), the "clearly", the straw man "colleagues" and the "bogus" are all signs of a person who is arguing at the air and concern me immediately. For whatever reason, be it an attempt to marry "science" and "religion," an attempt to satisfy his own needs, an attempt to sell his book, or something else entirely, he has published a very shady essay.