What Do Physicists REALLY THINK About Fine-Tuning? — Phil Halper & Stephen Meyer

Added: 2026-05-14

[00:00:00]Even among many of the atheist sort of thinkers I've spoken to, Richard Dawkins, Peter Millican, others, they've often said actually if there's one argument that has given me pause for thought, the fine-tuning of the universe is pretty remarkable.

[00:00:12]Now, do you in any way sort of question the fact of fine-tuning even if you perhaps are going to go in a different direction in terms of explaining that that fine-tuning? Well, I think it's better for me to reveal not what I think, but what physicists think because I've done some surveys with physicists about what they think.

[00:00:30]>> So, how about we do that?

[00:00:30]>> Yeah, let's find out.

[00:00:31]>> Okay. So, I've done two surveys. One was at a conference in Copenhagen organized by the Niels Bohr Institute. Had leading physicists there.

[00:00:40]And so, that was yeah, very very high top names in the field.

[00:00:46]But, a smaller sample size. So, I think we had about 80 replies. We've then teamed up with the American Physical Society and we've done what I think is the largest survey of physicists ever. I think it's 70 about roughly 1,700 replies we've got.

[00:00:59]Um So, why don't I reveal what the results are?

[00:01:02]>> Okay, you've come prepared. I've come prepared. So, this is what physicists actually think. So, let's start with the Copenhagen survey which we've actually published now. The other one has not been published yet, but I hope by the time this goes out it will be.

[00:01:14]Okay. So, we we Now, we gave them various options to explain the fine-tuning and we're going to go from the bottom up. Okay. And one thing to put this in perspective is just consider what how many scientists believe in God.

[00:01:28]Okay.

[00:01:29]So, if There've been several lot of surveys done in the US cuz that's where we have data so that's what I'm going to quote.

[00:01:34]For the general population it's varies survey to survey, but it's something like 70 to 85% believe in God. For scientists as a whole again it varies a bit so it's something between 30 and 40%. So, it's a big drop. And then when you go to what I call the eminent scientists, the top people in the field, they surveyed let's say members of the National Academy of Science, they got I think 7% believed in God. So, another big drop. Okay. So, here here are the results from our Copenhagen survey. Um the the least popular uh option by the scientists was selected as the intelligent design option. It got 3% support. Now, notice that's much much lower than even the numbers that believe in God from the the other survey, right?

[00:02:16]It's less than half. Um then So, that got 3%. The next one was necessity.

[00:02:22]Um so, this is the idea that the constant sizes have to be what they are. Right. So, there's no point arguing about, you know, how improbable they are. That there's some mathematical reason why they have to be what they are. You might not know what it is, And how And how many took that? So, that got 9%. Okay. Uh the next was a Darwinian selection. Okay. So, that got 10%. So, the idea here is we've seen this problem before. If you throw genes together randomly, you're not going to get a functional organism. And most I think most scientists think that Darwin solved that problem. Now, obviously, Stephen doesn't think so. So, this one's not going to be popular with him. But, um the idea is that >> Darwinian on a more sort of Yeah, the idea is that the universe can reproduce itself.

[00:03:05]>> I see. Okay. So, one way that's like, for example, Lisa Randall's come up with a particular mechanism, but you could imagine other mechanisms. But, the idea in Smolin's model is that the um a black hole can give birth to a new universe. So, if singularities are replaced by bounces, which it seems to be implied by some models of quantum >> us back to our previous conversation, but but Yeah, that there's some explanation in the evolution of the universe uh in previous states Yeah. that that allow that we find ourselves in one that is Yeah, it's select it selects for ones that can reproduce themselves. So, it's selecting for more black holes, not for life. Life just becomes a sort of happy byproduct.

[00:03:39]>> Okay.

[00:03:39]>> So, that's that's Darwinian selection.

[00:03:41]So, that got 10%. Okay. So, num number two, um I've I've I've admitted here no opinion and other. Okay. Um number two, do you want to guess what number two was?

[00:03:52]A multiverse?

[00:03:53]>> Yes. Multiverse was number two. Okay, so that got 24%. And just again, if just for the sake of those who perhaps don't know what we're talking about in that regard, could you perhaps briefly explain the multiverse hypothesis?

[00:04:04]>> Yeah, so we actually say it's anthropic selection in a multiverse. So multiverse is that it's like it imagine a lottery, right? Super unlikely that someone wins a lottery unless lots of lottery tickets are sold. If a lots of lottery tickets are sold, quite likely that someone wins a lottery. And then the anthropic selection comes in whereby so the idea is you could only observe the universe that has life-permitting values. So you will you have a selection bias. It's not what's the most likely universe, our universe could be incredibly unlikely. It's what's the most likely universe to be observed cuz you have to observe the one that's life-permitting.

[00:04:38]So so that's why we call it anthropic selection in a multiverse, right? So that was the second most popular sort of way of making sense of fine-tuning of the universe for life. Correct.

[00:04:49]>> Correct, yeah. What was the number one then?

[00:04:51]Any guess?

[00:04:52]Uh I don't know. Go on. I don't Okay, it's that the the constants of nature are brute facts that need no further explanation. That there's nothing to be explained That's different to to them being necessary.

[00:05:02]>> Yeah, yeah, no, it's the necessary is different to a brute fact. Okay. So necessary means they have to be what they are. So imagine like a coin flip, right? So you could take a coin flip and say, "Okay, it could land heads or tails. It landed heads."

[00:05:15]What's the grand metaphysical explanation for that landing? There isn't one. Just deal with it. It landed Okay. No, who cares, right? It's heads.

[00:05:22]That's what it came out as.

[00:05:25]>> And so it's just a brute fact. It's not that it had to come out heads. Whereas necessity means it has to come out heads, right? There's some reason why it had to come out heads. Right? So that that was our survey of the experts. Then when we did the American Physical Society, that's much broader, much much broader. We had, you know, 1,700 replies. And so there the the results are pretty similar, okay? They're not radically different.

[00:05:50]Um so intelligent design, I expected it to be I thought, well look, the population of the elite scientists, let's say 7% believing in God, and the broader scientific community is maybe 35% believing in God. So I thought it'd go up by five, but it only went up by three. It was 9% belief in intelligent design, okay? So it was number two at from the bottom rather than number one from the bottom rather than at the bottom, okay? Um then necessity actually was the one that got the biggest boost.

[00:06:17]Okay. Now we actually rephrased it. I should I should because when we spoke to American Physical Society, they went, "Ah, necessity is a philosophical term."

[00:06:23]So we rephrased it to there's a principle that sort of forbids fine-tuning. Yeah, that the laws are producing their their own fine-tuning arguments.

[00:06:31]>> yeah, yeah. Well, it's that there's some reason why they There's some reason >> features of the laws, whether they it be their initial conditions or >> don't say that cuz it is it's it's more that there's a reason why they have to take on the values that they do from coming from physics. Okay. Right? So that got 19%. So that that got the biggest difference between the the professionals and the and the broader one. Then Darwinian selection had 6% rather than 10% and multiverse went down a little bit, um 24% to 21% and yet again brute facts was up on top. Okay, now here's one of important thing I want to take away from this, okay? Because we're often told that you have to choose between an intelligent designer or a multiverse. Okay?

[00:07:17]And this is what physics is telling us, okay? But if you actually ask physicists what they think, they think that neither of these two options is Well, if you add up those two in both surveys, they came to less than a third. Less than a third back that option, right?

[00:07:34]And and and so actually physicists don't think you need to appeal to intelligent designer or a multiverse. Not not by a majority. I mean some do, obviously, right? So So this is important because the narrative that we're being told is that these are your two choices. And in fact, um many physicists think that's not correct.

[00:07:52]>> Okay.

[00:07:53]I'd just be interested in your response to this interesting survey that was done.

[00:07:57]>> I I think um it's an argument from authority.

[00:08:02]And it's an argument ad populum. Okay, we're going to take a vote, right?

[00:08:06]Nothing in what was said responded to the basic logic of the fine-tuning argument, which is that when we find fine-tuning as a feature of systems and we know how they arose, they invariably arose from the activity of an intelligent mind.

[00:08:22]So we could identify to see if the the consensus view of the scientists that there's nothing there to be explained, whether they would apply that reasoning to any other fine-tuned system that we might see in say our terrestrial environment. If a section of software had to be very finely tuned to produce a certain programming output, would we say, "Well, the software is just a brute fact of the system" or would we want instead to attribute it to a programmer? Similarly, uh if we saw that uh there were a whole lot of ways of arranging the parts of an internal combustion engine, but only very few of those configured just right will result in the engine working, would we want to say there's nothing there to explain?

[00:09:09]I I think if we're going to appeal to the consensus of a community, we also need to be aware of what the assumptions of the community are about how they are to practice their discipline. And this applies to both materialist and theistic uh scientists. And that is that there's been a long-standing convention in science from about the late 19th century, soon after the Darwinian revolution, that science must limit itself to materialistic explanations only. It has a fancy name, it's called the principle methodological naturalism.

[00:09:40]I think it's very much at work in the proliferation of naturalistic pre-Big Bang models, all the things we were talking about. But many scientists have been quite open and honest about the role of this convention in in affecting their own thinking about the God question. For example, Richard Lewontin, a really famous Harvard evolutionary biologist was quoted several years ago as saying, "We take the side of science." And he's talking about the the historic conflict between science and religion. He said, "We take the side of science in spite of its many um counterintuitive constructs, in sight in in sight in sight of its unsubstantiated just-so stories, think the multiverse, for example, um because we have a prior commitment to materialism." And he said that commitment is absolute. We cannot allow a divine foot in the door. So, you have something like the fine-tuning evidence, which as I've argued in the previous session, occurs repeatedly in attempts to model the universe without a beginning.

[00:10:43]So, you've got this very fundamental feature of reality that recurs we we recurrently encounter.

[00:10:51]And rather than saying something needs to be explained or we we say nothing needs to be explained or we come up with a multiverse theory. And yes, intelligent design is at the bottom of the heap, but it's at the bottom of the heap among a community of people who accept that it is their duty as scientists to limit themselves to strictly materialistic explanations only. So, I don't think we can assess the rationality of the fine-tuning argument by an appeal to the consensus of a community.

[00:11:18]>> a sense I'm also hearing here that that good scientists don't always make good philosophers of science. Then there may be some extra Yeah, yeah. They absolutely do not.

[00:11:27]>> And so, just polling is So, what what do you find >> Well, I've noticed when you poll philosophers Yes. the brute facts was the number one Okay, well that's interesting.

[00:11:37]>> So you can't appeal >> Okay. to to the to philosophical ignorance. No, hang on, hang on. Wait a minute, wait a minute. You're appealing to a consensus now.

[00:11:43]>> no, no, I'm not. Okay, cuz I'm not saying you have to believe in brute facts cuz that's most popular. I'm not saying that. What what I'm trying to do is is to correct the narrative because of course notice that when Stephen opened his argument up, he appealed to Fred Hoyle as a great physicist and of course he was. He's also the discoverer of the first set of fine-tuning parameters. I didn't interrupt you, right? Okay. Right. So peo- people you people appeal to authorities and so on when defending the fine-tuning argument and I think it's worthwhile pointing out what physicists actually think. I certainly don't think any scientific disagreement can be decided by a poll.

[00:12:19]Obviously not, right? But what we can do is say, "Look, people are saying this is what physicists think and they're misrepresenting what physicists think because they haven't actually done the research. And we have.

[00:12:30]>> What what right? I I I'd push back on that. In the back of of um of Luke Barnes's wonderful book with written with his atheistic supervisor from Cambridge in his PhD at Cambridge in physics, he has a list of all the leading physicists who accept that fine-tuning is something that needs to be explained.

[00:12:47]And so that first explanation is that it's just a brute fact. Maybe many don't, but the the fact of fine-tuning is something that's on the table. It's been established by leading physicists.

[00:12:57]And But it hasn't been established. This is something something that's been disputed. This is the whole point. All right, well let's go there.