I’m of many minds about this…

I’ve been meaning to refer to a new round of multiverse talk on the internet that arose a few weeks ago, mainly due to a new book by string theory promoter Brian Greene. (The book is getting good reviews.) Somewhere, out there in the multiverse, I guess I already have.

This was all kicked off for me by a post by Peter Woit at Not Even Wrong. He noted that had recently seen Lee Smolin give a talk at a New York museum in which (from what Woit could remember):

….he said that discussions of a multiverse containing infinite numbers of copies of ourselves behaving slightly differently made him uneasy for moral reasons. The worry is that one might be led to stop caring that much about the implications of one’s actions. After all, whatever mistake you make, in some other infinite number of universes, you didn’t do it.

Now, before I get to talking about that issue, I should mention that Woit (who certainly hates the string theory version of the multiverse for its untestability, but seems more open minded about other theories that lead to them) also links to a sceptical review of Greene’s book (“The Hidden Reality.”) This review is one of the best short summaries of the problem of string theory, and how those problems evolved, I have read. It’s well worth a visit.

And, again, before I get onto the multiverse and morality, Peter Woit’s post has a very good series of comments in which there is some discussion of whether the widely accepted theory of early universe inflation leads to enough multiple universes as a possibility anyway. In fact, one of the whole issues in Woit’s thread is that he complains how physicists do mix up the different theories that lead to multiple universes and act as if there is some connection between them all.

This is a good point. I would have thought that the type of multiverse with the real moral issue is the one arising from Everett’s many worlds interpretation of quantum theory. But string theory allows for so many universes that it seems you can get to multiple versions of yourself that way too (in fact, I’m not sure of this, but with more versions of yourself than Everett’s version alone?)

So, back to morality:

I’ve run out of time. Will continue later.

Continued:

Meanwhile, more detail of the issue of the multiverse and morality came up at Cosmic Variance, where physicist Sean Carroll noted a post at Huffington Post by Clay Naff (who I am unfamiliar with.) Naff argues that the multiverse violates the "Moral Principle" which he explains as follows:

It states that we should resist accepting any proposition that tends to disable moral reasoning, unless and until the scientifically interpreted evidence compels us.

I honed this principle in the context of my critique of religion, but it applies, for example, to the secular idea of the philosopher's zombie. The Moral Principle prevents us from accepting the idea that anyone else is a zombie who appears to be just like any other person, except that there's no real consciousness inside. If we were to accept that idea, there would be no moral barrier to torturing or murdering "zombies." In fact, it would be much like Hitler's dehumanization of the Jews.

Now, Naff doesn't actually spend any time explaining how the multiverse would corrupt moral reasoning, but Sean Carroll has a go at what his argument seems to be:

What he seems to be concerned about — although he never quite comes out and says it, so a bit of interpretation is required, and I could always be misreading — is the possibility that our moral intuitions could be undermined by the idea that there are an infinite number of copies of ourselves out there in the multiverse, some of them exactly like us and many of them slightly different, e.g. worlds where Hitler was victorious, etc. In such a setup, should we be concerned that morality is pointless, because every good thing and every bad thing eventually occurs elsewhere in the cosmos?

That seemed a fair guess. But Naff then turns up in comments and disagrees. His example of why the idea is dangerous is:

suppose that you truly believe that there are infinite copies of yourself “out there,” including every possible variation of your life history. Now, suppose I offer you a million dollars to play Russian Roulette with a gun that has five of six chambers loaded. Would it not be rational to take the bet? And so, would it not be rational to abandon “this” life at every frustration or mistake?

Carroll, before Naff's comment, argued that this should have no effect on morality at all:

The job of morality is to figure out what we think we human beings should be doing, which, as we’ve been discussing, does not reduce to looking at what actually happens in the universe....

I don’t think we should be concerned about that (even if it’s true, which it may very well be). An idea like this doesn’t “disable our moral reasoning” — in fact, it might be extremely helpful to our moral reasoning. If your version of morality depends on the assumption that what happens here on Earth is unique in the universe, then it’s time to update your morality, not to put your hands over your ears when people start talking about the multiverse.

Naff has to point out something important to his view in another comment:

The argument I am making has everything to do with the premature adoption of a conjecture as scientific fact in the popular consciousness. Can this do harm? History demonstrates it. Leave aside “Social Darwinism.” I presume that none of you would deliberately torture a sick child. Yet, early in the 20th century, the premature adoption of the scientific hypothesis that *starvation* could cure juvenile diabetes led to horrific maltreatment of already suffering children. You may scoff at the notion that MW as a worldview (rather than as a scientific hypothesis) can have terrible consequences, but I can only say that it shows a poor understanding of history, moral reasoning and/or the social impact of ideas.

What to make of all this? Some points:

First: it's surprising that in all of the threads, no one has mentioned that Everett himself believed that many-worlds theory implied a type of personal immortality, and it is possible that this even influenced his daughter who committed suicide.

It seems to me to be a little hard to argue against belief in the multiverse having no implications on morality, even though they are ambiguous. Score one for Naff.

Two: We've already heard some of the possible negative implications, but you can try and spin it in a positive sense. As someone says in the Cosmic Variance thread:

I for one, if given the option, would prefer to live in the most moral of all multiverses, and will make my choices to promote that end result… It’s like saying that because there are bad neighborhoods, everyone should stop trying to build good ones.

Also, as I noted here some time ago, Christian physicist Don Page is un-fazed by a multiverse, but in his paper "Does God so Love the Multiverse" (I still like that title) it seems he does not address the type of multiverse which sees multiple versions of the same person and what that implies for moral decision making.

Here's another idea: the idea of re-incarnation has some intuitive appeal if it is seen as a learning cycle, leading ultimately to the soul being incorporated (or re-incorporated) into the Divine. How does a multiverse tie in with that idea? Like parallel computing, does it mean a faster process of God becoming God?

But getting back to the negative: as someone else notes in the Cosmic Variance thread:

What I decide now will irrevocably select a branch for this universe from now on. Which branch would I like to be on?

How is that not a workable basis for a workable morality, albeit an openly selfish one?

This leads to my next point.

Three: When talking about morality and the effect of scientific and religious beliefs, there is an important distinction to be made between the general and personal. The thing about systems of morality or ethics that has always interested me is the motivation to personally act in accordance with the rules that everyone can agree theoretically should be followed.

A religion that believes in an afterlife with real consequences for how you have acted in life does provide a motivation to act morally, whether or not you can "get away" with it during life.

Similarly, belief in a multiverse may be unlikely to affect how everyone agrees we should ideally behave towards each other, but it is conceivable that it may (as in the last quote above) provide an incentive to act in accordance with whatever you can get away with now; or it may (as with Everett's daughter, or the Russian roulette example of Naff) make you careless as to whether or not you continue to live in this world.

On the other hand, does this really change anything from the moral reasoning that can already exist in an non-theistic vision of a single universe? It seems on reflection that a non-theistic multiverse or single universe both really contain the same lack of motivation for not getting away with what you can. The multiverse, may, however, have an additional incentive for the suicidally inclined (let's end this pained, hopeless version of me, and let the happy ones continue.)

Four: It always has to be remembered that over-certainty of anything, both scientific or metaphysical, can be the enemy of good moral decisions.

We would all agree that the world would be (or would have been) a better place if there were some less certainty of things like a heavenly reward in the minds of suicidal terrorists; or that witches with Satanic powers can wreck havoc in tribal community; or that the eradication of Jews was eugenically in the long term interests of humanity.

Yet, given that most versions of the multiverse are not really expected to be experimentally verifiable, this should be one belief on which it is easy to convince people to not bet even a small amount of money.

Five: As Bee Hossenfelder notes in the Cosmic Variance thread, there is one other scientific viewpoint that is here already, and which (in my view) is a much greater problem:

The “moral argument” would forbid you to accept any fundamental theory with fully deterministic evolution. If you have no free will, you’re arguably not responsible for your actions in any meaningful sense. Instead, it’s the initial conditions of the universe that are responsible. (Or the final conditions for that matter.) So. What now? Cut funding for everybody who dares to believe time evolution is fundamentally deterministic because the philosophical implications are sociologically difficult?

Good point, and I think there is little doubt that, apart from fundamental physics which implies no free will, the neuroscience and popular science articles that argue that we are not really in control of our decisions is deathly harmful to moral reasoning.

What's more, I have long thought, from various examples too numerous to list now, that the absence of free will is an idea that, although counter-intuitive enough to not think about consciously most of the time, has already seeped far into the collective unconscious of society, and for many people is affecting everything from half-conscious rationalisation of immoral behaviour, to depression.

I think this is the far more important issue regarding science and morality, and should be better addressed in education and popular philosophy.

The multiverse,meanwhile, remains a mere speculation, but one which allows for wild speculation which, I have to admit, I've always enjoyed.