Can Free Will be Saved in a Deterministic Universe? 

When PBS Spacetime uploads, I click. Not sure how much free will is involved there.

"I'm gonna end the episode without saying "space time." Actually, quantum mechanics forbids this.

"we must believe in free will, we have no choice"

Ivan Pavlov went shopping & heard a bell ring, and he said “damnit! I forgot to feed the dog!”

Came for the science, stayed for the existential crisis!

Hey everyone, I'm so excited about my first co-writing effort with Matt. (I'm especially proud of the last line!)

I flipped a coin to decide, and apparently I do have free will. Take that determinism! Oh wait a minute...

Probably the strangest situation is when you preform an action, seemingly by free will, and then you think back on your own history to find the events in your life that would've led up to such an action. With or without free will, we are ultimately products of our environment, and had I grown up in a different environment, even if I had the same genetics, I would've made very different choices due to experiencing different situations. Sometimes a chance happening somewhere can change your fate in a way far beyond what mere choice alone could do without that luck.

Things I took away from this episode: Atoms are not made of appleness

This channel has a knack for posing a straightforward question, and answering it so thoroughly that I come away more confused than ever.

13:19 "I am now going to exercise my free will to not end this episode with me saying "SpaceTime"..." - oops...

Been waiting a number of years for someone to come out with this topic at a sufficient level of information density and quality. Good on you.

Matt's closing statement that "Is free will an illusion?" is probably a poorly worded question is the most insightful answer I've heard so far on that topic.

This idea sent me into a 6 month existential crisis that I only got out of because I decided that, determined or not, experience is still novel to the person experiencing it.

I can't really comprehend nor understand what is even being described anymore

When I was very little I could enter sometimes in some very peculiar state of mind. It feels like a deja vu but isn't. It started with the question "what happened if I chose another action?" that popped in my mind every time I did something, anything, even moving a part of my body. "What happened if I chose differently? Would the future be the same? Do my actions have a domino effect going indeffinitely?" I knew nothing then about physics or quantum mechanics but it bugged me so bad. It got so intense that I felt tired when it was over. It's safe to say that now, 20 years later I still can't answer those questions satisfyingly

I see a video, I click. No free will here

Reminds me of Dr. Farnsworth's Death Clock. "So it predicts exactly the time you die?" "Well, it can be off by a second or two, what with 'free will' and all..."

What is the problem of having no free will if you have the illusion to have one.

This episode was definitely a "okay I need to rewatch that again to be able to make some sense out of it" type. I really enjoyed this shallow little dive into physics and philosophy, and I'm very interested for the quantum and consciousness sequel.

"In the end this is all semantics" I've noticed this is frequently more and more an issue the deeper we go. Our normal intuitions, semantics, and our way of perceiving and looking at things seems to break down.

I saw a video once where they explained destiny as not a line but a platform, and free will was just us moving in that platform. They put a mouse on one end of a table. The mouse was able to choose where ever it wanted to go on the table, but the table determined it would always end up at the other end of the table, no matter what the mouse chose.

I love how often whenever I challenge someone's free will belief, they respond by doing something random to try to demonstrate their ability to freely choose. One of my friends was getting frustrated once, so he said, "Oh yea, well I freely choose to do this" and he throws a shot glass at the wall and it shatters, and my other friend goes, "and now you freely choose to go clean it up." lol.

This emergent phenomenon was randomly determined to think that it does not have free will

I'm usually able to say "Space Time" when he does. You got me this time. Best ending ever :D

This is a fascinating discussion, but I'm afraid it'll never end.

Another killer episode! SpaceTime's been cranking out some bangers. When Matt was talking about "emergent phenomenon, conscious free-will can recursively influence the machine itself", that was some powerful stuff and reminds me of those people who say "Computers can only do what we tell them" and little do those people realize that self-modifying programs are pretty much Artificial Intelligence 101. I also like how, on a previous episode about determinism, you essentially related the relativistic block-universe to the quantum many-worlds and that's cool because I had a serious misunderstanding that the many-world somehow meant, every future and that's not true, it's "every _possible_ future" and that's a much different landscape of reality.

Is free will an illusion? Depends on what your definition of "is" is.

"I choose to believe what I was programmed to believe!"

Katsumoto: “You believe a man can change his destiny?” Algren: “I believe a man does what he can, until his destiny is revealed.”

"Apples aren't imaginary" is possibly the best argument in favour of free will I've heard to date!

I’ve been watching several RU-vids on this topic. Most place a ceiling on the potential complexity (wrt Science & Philosophy) and while possibly reaching a wider audience, fall short of crucial aspects. this talk breaks those barriers without becoming too hard to follow. A good result is that we are inspired to think more about the issue rather than given hard answers. This is, after all, Good Science.

Deep Thought : "I think your problem is that you don't really know the question"

Free Willy: about to jump out of the tank PBS Spacetime: Actually, quantum mechanics forbids this

Excellent discussion. I love the example of an apple's atoms not having redness or "appleness". Emergence in Systems Thinking/Systems Theory, the idea that a system can have properties that it's parts do not have, is key to this debate. The brain is not randomly processing information in a random way. It evolved to solve problems and make decisions that increased the chances of surviving long enough to pass genes onto the next generation. Each individual calculation by the brain is driven by deterministic laws of physics, but they all align to the state or memory of the system. Your brain has a mental model of yourself, the world around you and your place in it. A cosmic ray might might hit one of your neurons and cause a cascade of effects that pops a strange idea into your head. But if that idea doesn't conform to your values, beliefs and world view it will be dismissed. Our behaviour isn't random and it is justifiable to say we make decisions of our own volition without denying the deterministic nature of the parts that generated that outcome.

The conclusion that "free will" can exist if it is defined as an emergent property does not negate the fact that cause and effect are never broken, and that a "new thought thread" can never happen.

Reminded me of Christopher Hitchens' quip during a debate "Of course we have free will. We have no choice but to have it." Miss that guy.

This is by far one of my most favorite channels. It excites the imagination while educating you that reality is so much stranger than what it seems

It's very cool that you are exploring with this question (the meaningfulness of free will). Keep going! I believe this pursuit is worthy of more than a semantic argument.

Personally, I like the idea of the many worlds interpretation meaning that either the future is undeterminable, or every possible future is determined, since it means that you do actually have choice. The latter option, I feel, is also ideal for religeous individuals who believe in an omniscient entity, as it allows for that, whilst also not destroying the notion of free will. Also, I think it doesn't entirely matter whether or not free will exists. If it does, then great! If it doesn't, then there's nothing we can really do about it, so there's no point in worrying about it - as far as we need to be concerned on a day to day basis, we make our own choices that have an impact on the world around us, and the only way believing that there is no free will can truly impact you is if you let it stop you from living your life.

Hahaha, I was asking myself how were you going to end this espisode saying “Spacetime”. That was witty :D

This topic has been a particular interest to me so I'm really happy you covered it, love the work keep it up!

13:00 That covers just about all paradox (paradoxes?). If a tree falls in the forest and no one is around, does it make a sound? That depends on your definition of sound. Do you consider sound to be the pressure waves traveling through the air, or the perception of those waves by a conscious being? The "Ship of Theseus" takes this to the ultimately absurd extreme. It asks if an object that has had all of its parts gradually replaced remains the same object once it no longer contains any of its original components. You can't answer that question without first defining "identity" (and there will likely be more than one definition". Of course, once you define identity the question answers itself.

This is one of the best intellectual migraines Spacetime has given me in a while!

One of the best Space Times I've seen. Great ending.

Even if its quantum and unpredictable, its still not free will - its just a roll of dice.

Seriously, this literally ends with a quiz test.

One thing I appreciate is your self awareness. Many of your peers lack this trait. You da man

I read the title as “does physics negate free wifi”

14 minutes well constructed to say, 'Freewill as a concept is unknowable; much like consciousness.' I'm OK with that; it's great to continue pushing our knowledge and boundaries. It's also wise to remember this question has been and likely will be with us 'forever' (w/two little girls holding hands in a hotel hallway). Cheers Space Time

OMG this is the most complete analisys about determinism I've ever seen ! Most of the thoughts I had alone about it you just talked in it and made me feel a little bit more contemplated . Determined or not , thank you very much for this !!!

Headcanon Matt ends every interaction with the words "spacetime". "I'll take a double latte worth oat milk spacetime". "What?" "Uh... Sure. Here's your latte with oat milk." "Thanks. spacetime."

Randomness: Doesn't affect freedom, decreases reliability of choices. Unpredictability: Doesn't affect freedom nor control of the future. People want to feel in control. The things above won't help. For some, trusting the thinking algorithm to make good choices is comforting enough. Learning to choose better or overcome cognitive biases can increase this trust.

Hot take: as long as it feels like free will and is actionable like free will, it doesn't matter if it actually is or not via physics

6:30 This is the most interesting part. Nobody will probably read this, but I would like to bring up an important aspect to human consciousness: it's a multilayered consciousness. Think of it as a pipeline which produces the conscious experiences we have, where each step may or may not loop back to a previous step in the pipeline. Why this is necessary is because of the presence of metacognition, where we consciously act upon our consciousness, leading to abilities such as thought editing, memory reintegration, lucid dreaming, cognitive discipline and purposeful design of coping mechanisms. We're simply not just one mind, but many, slaving away in the factory that generates the experience of you.

Best video i've seen on the subject. Thank you very much !

When Spacetime uploads I simply click the video. There's no free will to prevent this from happening.

This question is very interesting and I have often thought about it. Having it analyzed scientifically has really broadened my horizons. Very interesting video.

Dr. Matt, l just want to say that your last line in this one is the best thing l have heard in quite some time.

"Can Free Will be Saved in a Deterministic Universe?" In that the universe is not deterministic, the question of free will is not threatened.

"We'll ignore what happened at the beginning of time, for today"

Probably one of my favorite episodes yet. I love how you tackle this topic in the sense that it's basically a paradox in itself and we know that more ideas or answers will simply create more questions and doubts about it. Keep up the good work!

question: why assumes that in the many worlds interpretation we would be "choosing" our reality instead of reacting to simply being in that instance of it? this seems to assume free will before the discussion of whether it exists.

All that exists is one gigantic free will choice. We are witnessing that choice. The choice To Be. I'm grateful that this was The Choice.

I absolutely love how you finagled the "Space-Time" ending into the video. Matt as always breaking all the laws

My free will is telling me it's not free, there is always a cost

Great, so if the apple is not an "illusion", my free will neither, and my identity neither, and so i didn't die crossing the teleporter, I feel better now... hmm well i'll have to go to bed and I think about that again tomorrow... which makes me remember about that video suspecting my identity is dying when i fall asleep...

We don't have free will and the universe insists that we argue about it.

Loved the last part about emergent phenomena , you made a great precisation ! Reductionist science has always been correct but that doesn't mean its always the full story...especially on deep , complex and not fully understood subjects as consciusness or free will. Electrons in your brain might not be forced to make you say "spacetime" as your last word in every video...but they might just be loving it !

I find it interesting WHY people have such a bias toward "free will" WHY is that?? I don't have a problem with living in a deterministic universe at all

I have to say, I was really reluctant to watch this video at first, but the intro definitely convinced me to give it a try x)

This is the kinda stuff that you think for a whole weekend without sleep and then stomp down to the "do not touch" zone.

Thought experiment! If I were to make a perfect quantum level copy of myself, put him and myself in 2 separate but perfectly identical rooms with telephones in them connected to each other, and tried to have a conversation with myself. Would I ever be able to converse? Or would we just keep interrupting each other endlessly saying the same thing at the same time?

That Laplacian demon was utterly terrifying. Was it predetermined that I would have to see that nightmare today? If so, curse you oh universe!!

The best answer to “What is outside the universe?” I've heard is: “The universe is by definition everything that exists, so nothing is outside of it by definition.”

It's useful to consider the word "will" in free will in the same way we think of "will power". Will power is a relatively recent evolutionary attribute, that gives us a significant survival advantage. there are deterministic ways to explain will power, but it's also reasonable to think that the brain could have evolved to take advantage of quantum randomness to get a little extra help in breaking pre-defined behavior patterns. this view of free will is real free will, the ability to make choices that are not predetermined. it doesn't contradict our understanding of motivation and psychology. it doesn't rely on appeals to the supernatural. and it's still actually pretty satisfying.

Best ending phrase of a space time episode so far.

Thanks I thought I was out of excuses to use for not doing my homework...

Ok so I listen to these to help me sleep pretty sure I’ve watched every one (and not cause they are boring or anything like that but imagining what all the geometry and physical processes looks like helps me sleep) but just as I was about to fall asleep he had to say “I’m going to exercise my free will to NOT end the episode by saying space time” so thanks for keeping me up

First, love that you did this episode - can be a risky subject, but should be addressed, and you addressed it pretty well, so kudos. Having said that, I have some quibbles, because... of course I do. ;) 1) I don't think the creation of NEW information is a requirement for agency, simply influencing the DIRECTION of information could represent a choice - or even just the ability to affect a probability distribution in a non-deterministic manner could demonstrate free will. If encountering a "Free Agent" (brain, or whatever) ALTERS the course of events in a manner that is not normally observed where no agent is involved, then that agent has made a free choice. They have taken a set of inputs and caused an atypical result. IE: They have acted on the information in a manner that demonstrates the ability to control, rather than be controlled by, the information. I don't think it's necessary to completely disconnect from a system to demonstrate free will, freedom to move WITHIN a constrained system is still freedom - and more importantly is the only presumption that makes any sense. The ability to create something from nothing is Godhood, not free agency... and a bit of an unreasonable ask in my opinion. ;) 2) On free will and randomness. I think this comparison is something of a problem. Since we generally define "random" as "unpredictable", free will MUST, to any outside observer, appear random. If an outside observer could perfectly predict the outcome from an encounter with the agent, then it can only be presumed that no CHOICES are being made by that agent, which doesn't necessarily mean the agent doesn't have free will, but only indicates they did not exercise it, or have already used it previously to "lock in" their future behavior, and aren't any longer exerting it) and thus free will in that encounter isn't even something that can be discussed. The observed outcome would be indistinguishable whether free will is present or not. The agent/event in question is simply acting as a transformation function and could be represented as a natural law (or perhaps a complex combination of laws, but same basic principle). Therefore, the question of free will can only ever even be ASKED when a non-predicted (ie random to the outside observer) outcome/event is observed. My personal postulate at this time is that the inherent non-deterministic nature of the micro universe demonstrates that free will is not only possible, but inherently present. The "apparent" deterministic "laws" we observe in the macro world (and the fact that they ONLY seem to apply at macro scales) are simply the results of emergent statistical principles like the "law of large numbers". That is to say, that the predictability of the macro world is not proof of a deterministic universe, only evidence that when you get enough free agents together that their GROUP BEHAVIOR becomes statistically VERY RELIABLY predictable. Basically, what I'm saying is that if I took a few billion people and handed them an egg crate and 12 colored eggs (each egg of a different color, but each person receiving the same 12 colors) and instruct each to put the eggs in the crate, the fact that the outcome is deterministic on the macro scale (I have 12 eggs in each crate) at the end doesn't demonstrate a lack of free will, only a set of restrictions on the range of choices available. Each person will likely fill their crate with a different color arrangement (micro scale). Again, from the final perspective the micro-world arrangements will appear random to an outside observer (the final result state no longer contains the information on how decisions were made, and therefore appears "random") and I can even make very reliably predictions about the overall arrangement patterns using the principles of statistics (like how many crates of a given color arrangement I can expect to see). Nevertheless, neither the predictability (or lack of randomness) of the end state, nor the failure to create a new/unpredictable outcome (like a crate with only 11 eggs in it) demonstrates a lack of free will. It only shows that we have lost the information involved in making those free choices by the time we see the results. In other words, I don't believe the existence of a deterministic macro universe precludes free choice, it only shows that those choices are constrained and reliably predictable on a macro scale, or that the information used in making the decision was lost or hidden... (not that I particularly subscribe to the idea of a perfectly deterministic universe as that has never been remotely proven except on HUGELY macro scales where individual "choices" would be so overwhelmed by statistical forces as to be no longer discernible from error margins anyways...)

Matt you deserve an award for the script of this episode, it was not just insigtfull but also fun and full of wordplay, thanks a lot for the great work, I would like to ask if you could make a video about emergence, both soft and hard emergence and if possible about the Landau-Lifshitz pseudotensor (you mention it a long time ago but haven't got to it yet)? I know you are super busy with all your work so sorry to bother but if you read this I will be very gratefull :3 hehehe

I've always felt that my ability to choose freely isn't really impacted one way or another by the fact that someone else already knows what I'm going to do, either because their spacetime trajectory gives them such a time-slice of the loaf universe or because they have sufficient knowledge of the particles in my brain to be able to predict. I have been told that I'm very predictable, even without special quantum insight, but I don't think that negates my freedom to choose.

Devs is a great show that touches on this topic. Recommended

What a show. Keep up the fantastic work guys

“Young man, in mathematics you don't understand things. You just get used to them.” ― John von Neumann “Invoking quantum effects is just hand-waving. Just means we don’t know." - Dennis Taylor: We Are Legion (We Are Bob) (Bobiverse Book 1) As a human, you do not need to understand free will, you just need to get use to it and believe you have it. As an engineer, you do not need to understand Quantum Mechanics - just need to get use to it.

My grade school teacher: "This is the kind of question that will bake your noodle." LOL

One of your best videos imo, great explanation

I picked the wrong video to watch after just waking up, I know that much! 😲 😂 🤣

Would love to see an episode of PBS Space Time postulating the existence of free will and determinism with CosmicSkeptic.

Reminds me of Richard Brautigan who ended a book with the sentence "I always wanted to end a book with the word mayonnaise. "

"Of course we have free will because we have no choice but to have it." - Christopher Hitchens You didn't have the free will to not steal, we don't have the free will to not hold you accountable ;)

How you talk about point 4 has always been how I've ever thought about this question. It seems nonsensical to me to say we do not have free will just because someone with all the information might be able to predict perfectly what we're gonna do next. Heck, I'm pretty good at predicting what my best friend is gonna do next, doesn't mean that isn't his decision.

I write this comment in free will, as resulting from mechanistic causes. Forcing free will to be supernatural is a circular argument against free will.

Roy: A Life Well Lived, makes a light hearted attempt at answering this question and is no weirder than the many worlds theory

Loved it. One of the only treatments of the topic that not only left room for non deterministic emergent processes, but also (although too briefly) unmasked the entire debate as having as its fulcrum a sloppy, ambiguous semantic antiquity that hardly begins to describe the actual miraculous enigma its supposed to represent.

The way he ended this episode deserves a nobel prize lol

Absolutely brilliant, the uncertainty principle blows my mind. What is remarkable is how well these explanations agree with the Buddhist understanding of free will and choice, that when we don’t use awareness then our lives become predetermined, only through careful observation of the mind can we begin to make more fully conscious choices to change things around us.

This topic usually is more likely to bring about epiphanous moments when under the influence of some good grass

Someone : « no one who claims there is no free will act as if they believe it »

That was /very/ good. And in some of those sentences, Matt reached Gabe-level delivery of condensed meaning. I'll be glad to read the script in the mail.