Sunday, November 25, 2007

Taking Science on Faith - Two Views

The New York Times published an op-ed by physicist Paul Davies on Taking Science on Faith. I like Davies, and I appreciate a scientist who is not afraid to admit he is a deist and write from that point of view. Based on his reputation, it seems that a scientist can have faith in something bigger without it corrupting his work.

Here is the beginning of the essay:

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.

The most refined expression of the rational intelligibility of the cosmos is found in the laws of physics, the fundamental rules on which nature runs. The laws of gravitation and electromagnetism, the laws that regulate the world within the atom, the laws of motion — all are expressed as tidy mathematical relationships. But where do these laws come from? And why do they have the form that they do?

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. Therefore, to be a scientist, you had to have faith that the universe is governed by dependable, immutable, absolute, universal, mathematical laws of an unspecified origin. You’ve got to believe that these laws won’t fail, that we won’t wake up tomorrow to find heat flowing from cold to hot, or the speed of light changing by the hour.

Over the years I have often asked my physicist colleagues why the laws of physics are what they are. The answers vary from “that’s not a scientific question” to “nobody knows.” The favorite reply is, “There is no reason they are what they are — they just are.” The idea that the laws exist reasonlessly is deeply anti-rational. After all, the very essence of a scientific explanation of some phenomenon is that the world is ordered logically and that there are reasons things are as they are. If one traces these reasons all the way down to the bedrock of reality — the laws of physics — only to find that reason then deserts us, it makes a mockery of science.

Can the mighty edifice of physical order we perceive in the world about us ultimately be rooted in reasonless absurdity? If so, then nature is a fiendishly clever bit of trickery: meaninglessness and absurdity somehow masquerading as ingenious order and rationality.

Although scientists have long had an inclination to shrug aside such questions concerning the source of the laws of physics, the mood has now shifted considerably. Part of the reason is the growing acceptance that the emergence of life in the universe, and hence the existence of observers like ourselves, depends rather sensitively on the form of the laws. If the laws of physics were just any old ragbag of rules, life would almost certainly not exist.

Read the whole thing.

Not surprisingly, some of the science bloggers find Davies' position to be hokum, at best. Brian Switek, writing at his Laelaps blog, is one of several who take issue with Davies' essay:

Much of the hubbub over this piece is Davies' use of the word "faith" as he applies it to "science," but Davies neglects to define his terms. This sloppiness, as noted before, does little but obfuscate the argument, especially since saying that science requires faith is anathema to many scientists (and rightly so). "Science" has previously meant merely a "system of knowledge" that could be extended to almost any topic, only recently becoming more narrowly defined as a system of acquiring knowledge about the natural world by use of the scientific method. Assumptions are involved in this process, but the assumptions cannot simply be taken on faith, faith not requiring any reason or development of systematic knowledge. When I write about evolution, for instance, I work on the assumption that natural selection is one of its primary mechanisms as the importance of natural selection has been sufficiently proven over and over again, thus I don't need to reinvent the intellectual wheel every time that I want to talk about evolution. This is not taking natural selection "on faith," but working on an assumption that has proven to be sufficiently consistent in its utility to describe how evolution proceeds, even being known as the theory of natural selection. Davies makes no such distinction, however, and I can't help but wonder if his intention was to inflame given that faith is one of at least two f-words (the other being "framing") that has more to do with the culture war between science and religion than scientific discourse.

Another science blogger, the highly regarded PZ Meyers at Pharyngula, argues that science requires no faith whatsoever.

Davies lost my respect for his thesis early on, from the first sentence actually, but I'll focus instead on this claim from his second paragraph: "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." Perhaps this is where not being a physicist has the virtue of a different perspective, because I can say without reservation that he's completely wrong — in a historical science like evolutionary biology, we have no problem when we encounter a phenomenon that isn't orderly or rational, and that has all the appearance of haphazard meaninglessness. We're accustomed to seeing simple chance as a strong thread running throughout biological history.

And . . .

Alas, Davies also brings up the anthropic principle, that tiresome exercise in metaphysical masturbation that always flounders somewhere in the repellent ditch between narcissism and solipsism. When someone says that life would not exist if the laws of physics were just a little bit different, I have to wonder…how do they know? Just as there are many different combinations of amino acids that can make any particular enzyme, why can't there be many different combinations of physical laws that can yield life? Do the experiment of testing different universes, then come talk to me. Until then, claiming that the anthropic principle, an undefined mish-mash of untested assumptions, supports your personal interpretation of how the universe exists and came to be is a self-delusional error.

I'm also always a bit disappointed with the statements of anthropic principle proponents for another reason. If these are the best and only laws that can give rise to intelligent life in the universe, why do they do such a lousy job of it? Life is found in one thin and delicate film on one planet in this mostly empty region of space, and even if there are other fertile planets out there, they will be nearly impossibly distant, and life will be just as fragile and prone to extinction there as here. Even on this world, all of the available environments favor bacteria over scientists or theologians, and said scientists and theologians have existed for only about 0.00001% of the lifetime of this universe, and are prone to wink out of existence long before we can get rid of one of the zeroes in that number. If I wanted to argue for a position on the basis of the anthropic principle, rather than trying to pretend that we live in a Goldilocks universe, we should be wondering how we ended up in such a hostile dump of a universe, one that favors endless expanses of frigid nothingness with scattered hydrogen molecules over one that has trillions of square light years of temperate lakefront property with good fishing, soft breezes, and free wireless networking.

Maybe Davies has faith in science, but I don't. I take it as it comes. I have expectations and hypotheses, but these are lesser presuppositions than what is implied by faith—and I'm also open to the possibility that any predictions I might make will fail. Perhaps if Davies weren't so obsessed with equating his religion with his science, he wouldn't be blind to the fact that most scientists don't see his god in the operation of the universe.

These two seem to represent a consensus among the science writers, as the collection of responses at Edge indicates.

It appears there are two main issues most people are focusing on -- (1) belief in the laws of science requires a leap of faith since we do not know why or how these laws came into existence; and (2) Davies invokes the anthropic principle to make sense of the universe.

The first point appeals to me in some sense. I am not content to say that these are the laws and constants, and they are what they are, so who cares how they got there. I want to know why. But accepting the laws does not require me to have faith (well, OK, at the quantum level it's all faith on my part because the math is insane). Still, I do want to know why the laws are as they are, and not even slightly different.

It seems to me that the main argument against the anthropic principle -- that the laws of physics are exactly right to create life and that any variation would have generated a completely different universe -- is that we have no other universes by which to make comparisons. How do we know some other set of laws or constants would not also have also created life? More Davies:

A second reason that the laws of physics have now been brought within the scope of scientific inquiry is the realization that what we long regarded as absolute and universal laws might not be truly fundamental at all, but more like local bylaws. They could vary from place to place on a mega-cosmic scale. A God’s-eye view might reveal a vast patchwork quilt of universes, each with its own distinctive set of bylaws. In this “multiverse,” life will arise only in those patches with bio-friendly bylaws, so it is no surprise that we find ourselves in a Goldilocks universe — one that is just right for life. We have selected it by our very existence.

This line of thinking borders on New Age crap to me (as much as I like Davies). I can see why the science folk don't much like anthropic thinking. The universe has existed for about 15 billion years, and the earth has been here for around 4 billion years. Humans have been around, as an intelligent species, for about 200,000 years. I do not think the earth exists as it does because we selected it.

We need a new form of thinking, which will likely require an outside observer to take an interior perspective on non-human matter (a kind of looking out from the inside), that is beyond the scope of science at this point -- and beyond the scope of anyone, I think (though some shamans in the rain forest might suggest that ayuasca allows this perspective).

I don't how and when this new form of thinking might be possible, but what we currently have reminds me of a dog chasing its tail. A lot of action, but no real answers to the big questions. Still, it's a kind of fun to watch the occasional dust-ups.


Unknown said...


I disagree with all sides in this because I think they are beginning with a presumption that matter is primary, or an Old Testament God is necessary.

But I'm writing because I think you (and others) are misinterpreting what Davies is saying in your last quote of his. I read him as saying that since life could not exist in a universe unsuitable for life, of course life finds itself in a universe fit for it.

So ... it is not WE that selected the earth, it is only in fit-for-life places where we would find ourselves. [Basically, I think Davies is saying what you'd agree with.]

But I think you and Davies are right to suppose that ultimately science is likely to find a set of tensions that (somewhat) explain the hard numbers and relationships of physical laws. But even then, with or without God, life will be impossible to explain and consciousness will remain a complete mystery -- except to wrongheaded physicalists with their tantalizing unprovable theories that rely on hocus pocus.

Unknown said...

Now that I've read the wiki article on Anthropic principle, it is evident Davies was careful (yet tricky) in suggesting a varient of the Weak Anthropic principle -- which is sensible -- and not the Strong Anthropic principle, which requires intervention.

Davies speaks of 'God's Eye View' just to tease us, I submit.

Anonymous said...

There is a difference between taking particular laws of physics on faith and taking the rational comprehensibility of the cosmos on faith. Specific laws of physics are falsifiable using the scientific method. The intelligibility of the cosmos, on the other hand, must be taken on faith. Any rational justification for the rationality of the universe is ultimately a circular argument.

Anonymous said...

I, too, appreciate Davies' openness to revealing his belief in God. I find it humorous that some scientists are so "faith-phobic". We all believe in something/Someone and to try to hide this reality is downright unscientific.