Tuesday, December 18, 2018

a many-worlds question for my philosophical readers

One version of the quantum many-worlds hypothesis suggests that, every time I reach a crossroads at which I have X number of choices, the cosmos splits into the number of universes that corresponds to the number of choices in front of me: if I have nine alternatives, then eight more universes are born such that I, in my universe, select Choice 1 while the other eight Kevins, in their universes, respectively select Choices 2 through 9. (It could actually be infinitely more complex than this, as I discussed in my frothing-metaphysics post over at Kevin's Walk, but let's keep things simple).

Given the above, I have a question, born straight out of the mind of Sam Harris, who has gleefully taken an axe to the tree of human freedom: if there is no free will, such that we're never actually making choices, could this be seen as an argument against the existence of many worlds? In other words, if it takes choice for universes to split into alternate universes, then can such splitting happen if there is, in fact, no choice?


SJHoneywell said...


First, I think Sam Harris, while he has a few good ideas, is a bit of a kook. The easiest answer to this is compatibilism.

The easiest example I've heard is this. If you and I are sitting in a room, you could get up and walk out. I could also drag you out of the room. The difference between those two ways of you leaving the room is essentially free will.

Anonymous said...

The problem is: what constitutes a branch point? a human choice--what hubris! Schroedinger's cat? there are two cats..one dead in one universe and the other live in a different universe. The multiple universe hypothesis is simply an ad hoc hypothesis to get out of certain difficulties in metaphysics derived from physics. And physics is epistemological not metaphysical to begin with. Reminds me of a kitten chasing a laser dot.


John Mac said...

I'm far out of my league in this discussion, but I use the many universes theory when I fantasize about time travel (hey, sometimes it helps me sleep!). Essentially, whenever you travel back in time you inevitably impact the "current" present. Seems to me that the mere act of creating a new future is tantamount to establishing an alternate universe. And there would naturally be an infinite number of possible universes.

Every path in life we didn't take leads somewhere...

Kevin Kim said...

On this blog, I've called myself a "closet compatibilist" on several occasions. I do, however, often waver between "compatibilism isn't rational" and "compatibilism is the only rational outlook." The paradox (if it is a paradox) of affirming both determinism and libertarian free will appeals to me, and I suspect this may be the route through the dilemma, but we have to admit it's a route beset by hazards.

Harris makes a strong case for hard determinism in his book Free Will. In the example of the guy who either leaves the room of his own volition or gets dragged out, Harris would argue that the man who leaves "freely" isn't really free because, within his head, there's a convergence of factors (brain states, etc.) that push the man to stand up and walk out, seemingly of his own accord. Harris sees the universe as basically material and, as such, causally closed, i.e., everything that occurs in nature can be explained by chains and networks of cause and effect, thus leaving no room for free will. Making an appeal to quantum randomness doesn't help the free-will argument because randomness isn't a sure foundation for intention: if one arrives at a decision via random means, one hasn't actually decided anything—one has simply stumbled upon a course of action.

In my own fumbling musings on this topic, I've come back, again and again, to the idea that unpredictability is the best marker of freedom. Orbital mechanics tends to play out deterministically; Newtonian determinism governs the motions of tiny objects like atoms and molecules, the rules of whose behavior can be described through physics and chemistry. But try predicting the exact path that a living being at the anthropic level—like a dog or a rabbit—will travel in its life, and predictability suddenly leaves the picture. I'm not saying that freedom boils down to unpredictability, but I'm suggesting that unpredictability is a marker for freedom, and it's more than just humans that possess some measure of free will. We like to talk about how animals are compelled by their instinctive impulses, making them un-free, but the zigzaggy nature of the paths they physically trace throughout their lives would seem, to me at least, to indicate that they are, in fact, deciding which way to go, which carrot to eat, which member of the antelope herd to tackle, etc. True: animals are still predictable enough that we can hunt them by deducing where they are from the trails they make. But we can't trace their footsteps with fine-grained exactitude.

I also see how freedom and strictures weave into each other when we talk about disciplines like art (or any other endeavor requiring any sort of skill, for that matter). Tiny young children create chaotic finger paintings that all have a certain sameness that marks them as the products of children. As these kids learn artistic techniques—how to handle light, shadow, perspective, mood, etc.—the kids' works begin to truly differentiate themselves, and great art can be the result of all that effort, focus, and training. Such excellence can only come through discipline, and the paradox is that that discipline confers a certain freedom. The first "Kung Fu Panda" movie illustrates this when the master tells Po he is "free to eat." Po's discipline-through-training has given him the power of choice, including the freedom not to eat, which is the choice Po makes at the end of that scene.

So the seemingly paradoxical interweaving of freedom and strictures also points toward compatibilism, in my opinion. Freedom operates in and through strictures. Somehow, and I don't know how, these conditions coexist.

Or so I believe when I'm in a certain mood.

Kevin Kim said...


I'm sure you're aware of the éminence grise Daniel Dennett, a philosopher who sounds to me like a potential compatibilist bud of yours. Assuming you're a compatibilist, that is; you didn't actually say whether you were.

Kevin Kim said...


I agree that, thus far, we've had no empirical confirmation of any of this many-worlds speculation. The math seems to lead us in one possible direction, but there may be a crypto-Platonic assumption that, if something can be sketched out in the apodictic realm (read: something approaching the realm of Plato's Ideal Forms), then it can (or must?) exist in the material universe. This reasoning does work on occasion, e.g., when using Einstein's math to extrapolate the existence of black holes. But it's not a 100% reliable method, to be sure. Have we, for example, actually seen cosmic strings yet? So far as I know, they've only been posited theoretically, not actually verified.

So basically I'm voicing, in a long-winded way, agreement with (what I think is) your central point.

Kevin Kim said...

John Mac,

I've seen sci-fi stories, like "Back to the Future II," that deal with the idea of going back in time, altering history, and thereby creating a "split," or at least an alternate version of "original" history (where "original" depends on the point of view of the time traveler). One question that the story writers have to deal with is whether, in altering history, one is (1) creating a true split such that the original timeline still exists but runs parallel to the new one, or (2) shunting history onto an alternate track while also erasing the original timeline. Notice that option (1) doesn't actually solve whatever problem it was that necessitated time travel in the first place.

Most of these SF movies also seem to assume that there's a "best" timeline among all possible timelines—usually the timeline in which the heroes win the day. The sitcom "Community" liked to joke around with the idea of a "darkest timeline" scenario, the worst of all possible worlds, and some of the characters would wonder aloud whether they were actually living in that timeline right now.

Another time-travel scenario that gets a lot of play is the "causality loop," which might be the only way out of the so-called "grandfather paradox." The GP is a paradox that occurs when you go back in time and kill your own grandfather. Now that you've done so, it's impossible for you to have been born, and yet there you are, back in the past, killing Gramps. To get around this problem, some sci-fi writers posit that the time traveler is now caught up in a "causality loop" in which this part of the timestream branches off, loops back into the past, and circulates like that forever (whatever "forever" means in this context). I don't think the causality loop actually resolves the paradox, but these are sci-fi writers, not actual scientists or philosophers, pondering the problem.

The "Star Trek" TV series dealt with causality loops, and so did the movie "Groundhog Day," in which Bill Murray is caught in a Hindu-style samsaric causality loop that can't be escaped until his thoughts and behavior become enlightened. In these scenarios, the way to escape a causality loop is to figure out how to behave differently, thus breaking the cycle.