Sunday, November 25, 2007

Faith in Science

Paul Davies, a physicist at Arizona State University, wrote an op-ed piece in yesterday's times taking physicists to task for the manner in which they have either accepted certain base assumptions in physics as being inviolate, or having constructed elaborate meta-explanations that further confuse matters. While I agree with the conclusions Davies reaches in the last two paragraphs of his essay, I took some issue with how he got there. Follows is a conversation from my news group, in which I put up an initial response which was in turn responded to, and my recent riposte. I like what I wrote, but if more comes of it, I'll post it as well.

at first I thought this was interesting, but I think the arguments are a bit flawed, he makes some comments that are simply handwaving. It really seems like he is equivocating until the very last few sentences...I would have liked to hear his conclusions stated more up front.

The use of phrases like "meaningless jumble of odds and ends haphazardly juxtaposed" and "just any old ragbag of rules" undermines his argument because they are essentially meaningless, or worse yet, suggest either the presence of something that has lead to this indeterminate state or a complete nihilism. They also appeal to something like a vlugar sentiment, "oh, haphazard jumbles or old ragbags are bad things that can't be studied". maybe part of the problem is being unwilling to look at those things as possibly interesting phenomena, themselves. But he says that if the laws were "any old ragbag", life would certainly not exist. If he means we shouldn't treat the laws as inviolate, inscrutable, and utterly holy, then fine. but what a weird way to express it.

I also think he ignores some very significant points in philosophy, such as Hume's arguments against making such assumptions, including the assumption of causality. Ultimately, we have to accept that these assumptions are part of the limits on human reason, and when they are violated, that gives us a hint that a) there is something new and more interesting to study, and b) assumptions of causality are not necessarily going to hold because there are always possible elements of which we are not aware.

really, i think davies' essay should be asking a somewhat different question - not how can we make an internally consistent set of physical laws, but rather, what is it that makes our laws take this form? as in, these are products of human reason operating on human observations, and the perspective we are working from is inevitably the human-eye view, not the god's-eye-view. the laws of physics should be treated as the human-laws-of-physics, and I think at that point, the answer to why these laws hold might become a little more clear. ultimately, i think the problem of faith in science and religion can be understood more clearly in these terms, as both are rooted in the limits of human ability.


The response (left anonymous):
No amount of reading Hume is going to change what basic science is.
Science is science. Even if physicists were to drop everything to ask
why it is that their rules are the rules that they are, at the end of
the day they're still going to be stuck with some set of rules and
testable hypotheses that they can get paid to test. Also, he's not
asking "how can we make an internally consistent set of physical
laws". He is questioning the basic assumption that science has some
kind of ultimate say in the way things are. Also, I think in the
context of this piece "meaningless jumble of odds and ends haphazardly
juxtaposed" is perfectly meaningful. I also don't think saying
"haphazard jumbles and old ragbags can't be studied" is entirely
vulgar. Science is the study of the natural world and in the natural
world we don't encounter the haphazard jumbles or old ragbags that
Davies is referring to. Of course that could just be a bad

Here's what I found interesting: one implicit assumption that Davies
seems to make is that science is concerned with finding out the Truth.
Depending on who you ask you will probably get different opinions,
right? I personally think that science (as a thing, or methodology,
or entity) is NOT concerned with the truth. The fact that you can
publish papers in Nature and Science with p<.05 should be some
indication of that. There's always a margin of error. And there's
always the possibility that some discovery will invalidate your study.
But life goes on.

And my more extensive riposte:

I think you may have misread my response and I, at least, have a very different reading than you of Davies' claims. First - I didn't make the claim or hope to imply that reading any Hume changes what constitutes basic science - however ever since Hume first made his case about causality in the 18th century, science has had to deal with the very serious problem he raised - that no matter how much you observe about a phenomenon, you cannot know of all the causal relationships at work in creating what you've seen. You make this same point at the end of your response - nature publishes studies with p<.05, which means there is a statistically possible alternative occurence, even if we are extremely confident that the data we find is valid and that it supports an interpretation we offer. and of course, there is the old saw of "correlation does not imply causation". This is a very important aspect of any scientific work - that no matter how much we observe and test, we are probably missing something and have to be willing to accept that possibility - it's the blessing and curse of ceteris paribus. There have been many scientific and philosophical examinations of this situation and the role it has in our ability to conduct useful and effective science.

But this does not mean we should throw our hands up, bend our heads and carry on sadly accepting that "science is science". I think that is almost cynical - science is in constant flux, constantly questioning its assumptions, going through upheavals and revolutions, etc. Davies seems to insist that scientists are in fact doing just that, to their own harm - they are not trying to create "an explanation from within the universe and not involve appealing to an external agency." I think he pretty clearly states, in those last two paragraphs, that he does hope for internal consistency for physical laws. He also states pretty clearly that his issue is with scientists claiming that their explanation are free of faith - I don't really get the impression that he is calling science-as-ultimate-explanation a canard. Again, this is borne out by the last two paragraphs, which I think are mostly on the mark.

Davies's use of those phrases that I took issue with seems to be rooted in his frustration with the possibility that a nihilistic streak is becoming the base assumption behind the scientific endeavor. But I also think it is incorrect to use the term "meaningless" in the first instance - I think there is a solid case to be made that the universe is not intrinsically "meaningful", but is only so with regard to organism in it that can deal with "meaning". One might think this is esoteric philsophizing, but I think it is entirely relevant to science, particularly with regard to many things, intentional phenomena and information theory to give just two examples. Also, the term haphazard implies some kind of agency engaging in a careless behavior, and the altrernative is thus a meaningful, careful arrangement of the universe by ____. This is surely not what Davies wants to suggest is the right thing for scientists to think - and he explicitly says so at the end. I think it is perfectly possible to look at the universe as a meaningless hodgepodge of things haphazardly juxtaposed because that may just be what it is - that is in fact a question science is equipped to examine and answer. When you say that in nature, we don't encounter haphazard jumbles or old ragbags, you're right because that is not a very articulate or rigorous way to refer to the things we see - so instead we use nice phrases like "emergence", "chaos", and "non-linear dynamic systems".

Davies ultimately says that the laws of physics are themselves something that is subject to examination in a scientific context, so that we can work away from any turtles-all-the-way-down type explanations. I think that this is a fruitful domain of future research, where physicists will have to join with cognitive scientists (not a self-plug - this has already been happening, as in the work of Roger Penrose) to examine those rules within which they are operating, how they arise, and how they are part of the process by which physics is done (or as Davies says, are regarded with universe as "part and parcel of a unitary system"). What I think Davies ultimately wants to say is, stop trying to pull the physical laws of the universe out of the universe. Which I think is something we can all agree is an entirely appropriate thing for physics to do.


No comments: