? about Steven Weinberg's view on theroretical prejudices

[phinds]

I'm just finishing up Steven Weinberg's "The First Three Minutes" and I noted with some bemusement that in the middle of page 119 he has the following statement:

"The great thing is not to be free of theoretical prejudices, but to have the right theoretical prejudices." [bolding is mine, not his]

Now it seem to me pretty clear that the problem here is that one is likely BY DEFINITION to think that ones theoretical prejudices ARE the "right" ones. That's sort of part of the definition of prejudice isn't it; something that ones just KNOWS is right whether it fits the facts or not.

Do other theoretical physicists share this point of view, that anyone knows of?

It seems to me that this is a wrongheaded approach, but Weinberg is no slouch so maybe I'm missing something in all this.

Comments?

 

[bcrowell]

Hard to tell exactly what Weinberg meant without the context. Real science is nothing like idealized textbook science. Often scientists decide they're going to prove X is false because somebody else claimed X, and that person is a (*&#&^% idiot. There's nothing wrong with this as long as everybody plays by the rules, doesn't falsify data, etc. People also have all kinds of philosophical and aesthetic ideas about how things should work, and that guides them in their guesses about which avenues of investigation to pursue.

-Ben

 

[marcus]

...
"The great thing is not to be free of theoretical prejudices, but to have the right theoretical prejudices." [bolding is mine, not his]

... me that this is a wrongheaded approach, but Weinberg is no slouch so maybe I'm missing something in all this.

Comments?

as long as you are asking for comments...I didn't look up the context (the book is upstairs) but here's my take.

I've seen Weinberg speak and he comes across as tactful and modest. He will say things that might well upset or antagonize some of the audience but he chooses his words well so as to make it very gentle, maybe with a touch of self-deprecating irony. or some humor.

He has great confidence and selfesteem but he is not "in your face" with it.

So I think he may have been talking about INTUITION. not "prejudice"

INTUITION ... well you know what it means. An inarticulate part of your brain does part of the thinking for you. It would be tiresome or even impossible to put into words how you come to some conclusion. You can't spell out all the steps in the argument. You can't say exactly why but you have a hunch.

You find out by watching people over time who has the good intuition and who does not.

Over and over Weinberg has been ahead of the moves. He has shown good intuition.

He doesn't want to brag, or sound like he is putting undue importance on some mysterious hunch faculty. So he DEPRECATES intuition by calling it "prejudice". A humorous or pejorative (self-mocking) word for often-brilliant intuitive hunches that guide a good researcher.

Prejudice is like intuition in the sense that you cannot justify it rationally. And strong intuitions that persist over a considerabe time can begin to look like set prejudices.
But they are not the same. I think he is being a little droll in his wording.

Just my two cents.

 

[phinds]

Interesting thoughts, guys. Thanks.

 

[narrator]

Prejudice can be a pragmatic thing or it can be an emotional response. I can't see Weinberg promoting the latter.

 

[twofish-quant]

Now it seem to me pretty clear that the problem here is that one is likely BY DEFINITION to think that ones theoretical prejudices ARE the "right" ones.

That's not true.

That's sort of part of the definition of prejudice isn't it; something that ones just KNOWS is right whether it fits the facts or not.

Not necessary. What Weinberg is talking about are rough guesses that you work on in the absence of facts. One thing that happens in physics is that sometimes the facts change faster more than theory.

It seems to me that this is a wrongheaded approach, but Weinberg is no slouch so maybe I'm missing something in all this.

Don't see what is particularly wrong with it.

 

[twofish-quant]

I've seen Weinberg speak and he comes across as tactful and modest. He will say things that might well upset or antagonize some of the audience but he chooses his words well so as to make it very gentle, maybe with a touch of self-deprecating irony. or some humor.

Also there are lots of different ways of doing science, and you'll find that scientists themselves have different philosophical views.

INTUITION ... well you know what it means. An inarticulate part of your brain does part of the thinking for you. It would be tiresome or even impossible to put into words how you come to some conclusion. You can't spell out all the steps in the argument. You can't say exactly why but you have a hunch.

Or sometimes you can say exactly why. For example, in the absence of any other evidence, I would expect \omega_0 to be some nice round number like 1 or 0. I'd also expect that the speed of light is constant. Those are theoretical prejudices, they can be countered by fact, but if you have to guess, you can pick the numbers that give you the most symmetry.

Also there are some other prejudices. For example, I would expect that tomorrow the sun will rise, and the Earth won't get swallowed up by a giant space squid. That's ultimately a theoretical prejudice that the rules of the game won't suddenly change, and what makes that an interesting belief is that sometimes the rules of the game *do* suddenly change.

The problem is that if you have no guesses and assumptions about how the world works, it's really hard to be able to say anything.

You find out by watching people over time who has the good intuition and who does not.

Also one thing about a good theorist is that a good theorist is not necessarily *right*. It's important for a theorist not to believe in their own theories.

So he DEPRECATES intuition by calling it "prejudice". A humorous or pejorative (self-mocking) word for often-brilliant intuitive hunches that guide a good researcher.

And sometimes those hunches end up being wrong. Or right. There is a fair amount of luck involved here.

 

[twofish-quant]

Prejudice can be a pragmatic thing or it can be an emotional response. I can't see Weinberg promoting the latter.

I can. Theorists tend to be extremely emotional people. Sometimes you end up believing something because it *feels* right, and that's your subconscious figuring out something faster than your conscious mind.

 

[Chalnoth]

It seems to me that this is a wrongheaded approach, but Weinberg is no slouch so maybe I'm missing something in all this.

Consider, if you will, that the search for mathematically-beautiful equations led to both General Relativity and the Standard Model of particle physics. While neither theory was without experimental support, experiment only brought theorists part of the way. The rest was obtained through a theoretical prejudice that the equations that describe nature must be simple in some sense. And both theories have been remarkably successful, with no experimental deviation yet detected despite vast improvements in experimental accuracy.

 

[phinds]

Consider, if you will, that the search for mathematically-beautiful equations led to both General Relativity and the Standard Model of particle physics. While neither theory was without experimental support, experiment only brought theorists part of the way. The rest was obtained through a theoretical prejudice that the equations that describe nature must be simple in some sense. And both theories have been remarkably successful, with no experimental deviation yet detected despite vast improvements in experimental accuracy.

I think that's a bit more general than what I was thinking Weinberg meant, but none-the-less it's a great point and I appreciate your reminding me of it.

 

[enotstrebor]

I think that's a bit more general than what I was thinking Weinberg meant, but none-the-less it's a great point and I appreciate your reminding me of it.

Did Einstein succeed by having no prejudices , quite the contrary, he was driven by them and so the great thing is to have the right prejudices.

Error A) the popular opinion is that the scientist should look at things without prejudice (scientific like) when historically successful scientist had strong prejudices that drove them to there success.

Error B) the popular opinion is that the scientist should look at things without prejudice (scientific like) but scientist are human and humans have prejudices so no-one truly looks at anything without prejudice, so success just means having the right prejudices.

Choose Error A or Error B or both depending on your "scientific view" of people.

 

[Chalnoth]

I think the important thing to bear in mind here is that correct prejudices or no, the really important thing is to let the evidence lead, and not to get too attached to any specific idea without good evidence to think it's correct. As long as people don't collect into groups supporting one or another unevidenced idea, then there won't be any problem with prejudices, as different scientists will have different prejudices, and the right ones will be validated by experiment.

 

[PAllen]

Einstein offers a perfect example of good and bad prejudices. For a couple of decades, his prejudices motivated him to stubbornly go where others didn't, to great results (especially GR, where everyone else was looking for a minimal path to a Lorentz invariant theory; note that Hilbert jumped onto Einstein's bandwagon only in the year or two before completion, and had the benefit of Einstein's visit and lectures). Unfortunately, Einstein refused to modify his prejudices, leading him to produce essentially nothing of value after 1935 (though meant as an attack on QM, I consider the EPR paper as a valuable contribution spurring understanding of entanglement).

Minor caveat: Einstein did do some significant work on GR in the late 30s and 40s with Infeld and Hoffman; but this was refinement of existing theory.

 

[phinds]

all good points ... thanks