Free Will: Does It Exist?

0:00Hi, I'm Wendy Zukerman and this is Science Versus, the show that pits facts against free will.

0:11Today on the show, does free will exist or is it just an illusion? It's a debate that scientists and philosophers have been having for a very long time, but now the internet has entered the ring. There's a meme that's been going around social media and in these videos you'll see people saying, I just remembered I have free will, and then they do whatever the hell they want. In one, there's a guy who dumps all his silverware out into a drawer and mixes it up. He doesn't even sort the spoons from the forks. In another video, you'll see a man eating potato chips and then climbing a ladder to his attic where he sits on a stool and continues eating potato chips.

0:53But then he'll blink like a goat. So on the one hand, you have this celebration of our freedom, our free will, our ability to control our destinies and eat potato chips and bleat like whoever we want. But what if that freedom isn't real? There are pockets of the Internet telling us that basically everything has been destined before you even think of picking up a fork. I think free will is an incoherent idea. We know that it doesn't exist, and we know that what people think they have is an illusion. I don't think we have a shred of free will. If this sounds mad, it's not. Going back decades, scientists have been publishing papers showing that free will might not exist.

1:40So are we kidding ourselves if we think we're freely making decisions? That I'm the one deciding to tell you the science instead of going, or bleed. Anyway, I did that. I made the choice to do two animal sounds. Or did I? Today we find out. Because when it comes to free will, you may think you have the power to decide to... But then there's science.

2:09Science vs. Free Will is coming up just after the break.

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3:38Welcome back today on the show. Free will, does it exist? Meryl Horne, PhD, is going to tell us all about it. Hi, Wendy. Hey, Meryl. Yeah, we're going to crack this whole free will thing. That's great. Well, do you think we have free will, Wendy? From what I know, I think it probably is an illusion, but it's such a good illusion that I don't know how we move on from that. Obviously, I think I have free will. I think I make choices. so how do you get behind that mirror i mean that's what the science is helpful for right you don't have to just listen to us like philosophize about do we do we like let's let's look at the science exactly so where do we begin how do we can we get can we get behind the mirror or is it just philosophizing i think we can i think the science will actually help us see like, yeah, what's going on kind of behind the scenes.

4:39Okay. But first to just kind of set the stakes, you know, this might all feel like some silly little thought experiments, but the answer here does actually seem to matter. So like there've been some psychology experiments that get people to read something crapping on free will, like something that says, quote, science has demonstrated that free will is an illusion, unquote. Okay. And then the scientists see if reading that thing changes people's behavior. And these studies find that people will act worse. They're more likely to cheat, less likely to help other people, and more likely to be aggressive after reading stuff like this.

5:20Wow. Which makes absolute sense. If you tell me by the end of this episode, I don't have free will. I mean... You're just going to be an ass. I don't have a choice. Is that the idea? Is that the idea? What is free will? I guess. Is that it? That I just do not have a choice? Everything is predestined. Well, Leah, let's take a step back maybe and like get some terms straight. I don't think it means you will be an asshole. Okay. But we could say, like, let's look at what. Any more than you already are. Okay. So, yeah, here's one handy definition that's used by some scientists. Okay. So, okay, first there needs to be a choice involved.

6:03So you're at the ice cream shop trying to decide between the chocolate and the caramel. Right. Which for me is a tough one. Chocolate, obviously. What? Caramel is pretty good. But if I have free will, it means that I am the one deciding. Like it's not a random choice either. The idea is that I have the freedom to really pick between these two different flavors. Yes. Yeah. So sounds good. That's basically our definition. Oh, okay. Yeah. But there is a world where you're not actually making that choice. Yes. So that's the big question. Like, is that feeling of having a choice real or not? Because for centuries, there have been challenges to this idea.

6:46So basically, as soon as we started discovering the laws of physics, you know, the fact that we have gravity and all these forces that can explain why things do what they do, we've gotten this picture of the world that's like a clockwork. You know, the reason something happens is because something right beforehand made that happen. And you could also kind of predict what's going to happen next by looking at these forces and you can explain like why things do what they do. Right. If you put a ball down a hill, thanks to gravity, you know it's going to roll down. That's a long bow from I don't pick my ice cream flavors.

7:24is yeah well so there is a lot of dots to be connected there uh but our bodies you know your body choosing that ice cream flavor is just made of a bunch of molecules were made as the same stuff as that ball and so in theory couldn't we predict like what all our bodies are going to do next just by looking at those molecules and then like applying the laws of physics biology neuroscience whatever. I talked about this with John Dylan Haynes. He's a professor at a neuroscience center in Charité, a medical school in Berlin. And he had a sort of visualization for how to imagine this in this like clockwork.

8:04Okay. You're kind of like in this, on this rail, like a, like a carriage or a train. And you're in this, on these tracks and there's no way of escaping the laws of nature. You're kind of constrained to the path that the world is going to go. So going back to that ice cream decision. Ideally, you'd be able to see what's going on in my brain as I'm trying to make this choice and see, can someone just looking at my brain sort of figure out what I'm going to choose in advance? So John told me about this experiment that kind of changed everything. So it's the 1980s, and there is one scientist, a neurophysiologist, who ends up doing this pretty famous experiment.

8:46Yeah, so the person who started this whole thing off was Benjamin Libet. So this guy, Benjamin Libet, he wants to kind of see what's happening in our brains as we're making just one stupid little decision. Okay. And the idea is that you would see the patterns of neurons firing or whatnot and that they would have fired as if to say chocolate flavor. But you only consciously decide chocolate after those neurons have fired? Is that what we're looking for in the brain? That's the idea. Yeah. Like, what's the order of events here? Can you see any signs of chocolate neurons firing before people are like, I made my decision to get the chocolate ice cream?

9:34That's basically what he's going to do. Okay. Interesting. But instead of bringing people into an ice cream shop, he does something much more basic. So imagine if you're in this experiment, He has you come into the lab, you sit down in a chair, and he gives you these instructions. You see your hands, and what I want you to do is sometime when you feel spontaneously the urge to flex your wrist, please do that. And then you flap your hand, like, just up and down. Exactly, exactly. Like a wave. Okay, a wave. A wave with your whole hand. Got it. Okay. So whenever you feel the urge, flap your hands.

10:08But meanwhile, he wants a way to track exactly when you made your decision. so he puts this thing on the wall. Like a clock, just with one single point, like a simple clock. Okay. And I ask people to remember where the point was when they made the decision to move now. I'm going to flex. I'm going to do it. I'm going to do it now. And you flex it. And then later the person would say, like, yeah, I made my decision to flex my wrist when the point on the clock thing was at, like, the 3 o 'clock position. Yes, precisely. And then meanwhile, Labette's got this EEG going on. So electrodes on the person's scalp that can measure electrical activity of the brain.

10:48Okay. And then he can also see when they flex their wrists because he has something else that like reads out muscle activity. So now he has the time people say they made this decision. Yes. And then he has the time they actually flex their wrists and he has those brain signals throughout this whole time. So now we're kind of ready to see, like, what is going on. Like, if we are the ones calling the shots, if I have the power to flex my wrist now, you'd expect to see a certain pattern of events. First, you make that decision to flex. You're in control, and then the brain comes later. And that was kind of what he was expecting.

11:25What he found was that this brain signal happened even before people made up their mind. And that's the paradox. so that he would see activity in the brain. Then people would think, I'll flap my wrist now. Yeah. Yeah. He sees a little like blipty blip in the brain before people say they decided to flex their wrists. It's not that convincing though because, I mean, what was it? He found it was like a couple of seconds difference. Maybe people just didn't look at the clock properly, right? It was even less than, yeah, it was half a second. Half a second. Different, yeah. Different. That could be the time that you consciously decide to flip your wrist and then you look up at the clock, right?

12:12I don't think my free will doesn't exist thanks to this study. Yeah, no, lots of people had criticisms like this, right? Right. And so, you know, this old experiment from the 80s wasn't like the last word on the question of free will, of course. Like, John actually decided to do a more modern take on this experiment using, you know, newer equipment. So, yeah, now it's the early aughts, 25 years later, and he does fMRI. Yes, this is what we need, yes. So now you can get a more detailed picture of, like, what brain activity is happening where, and they can use these fancy computer programs to analyze all that data.

12:52Oh, this is excellent. Yes, yes. So John and his team bring in a bunch of volunteers, 14 of them. So what they were told to do was to spontaneously at some point they could decide on themselves to decide between a left or right button and then to immediately press the button. So left button or right button whenever they feel like it. And then John, meanwhile, Whenever they make the choice. And then John's, meanwhile, John is getting all this data from the scanner and then he looks at the results with his student. And it turns out that they did replicate that old experiment from the 80s. It held up.

13:30And they found something even more extreme. So he sees a brain signal that was happening even earlier, whereas before it was a half a second. Difference between when they started to see the blip and when people said they made the decision. Uh-huh. Now John could see a signal seven seconds before people said they made the decision. Yeah. Seven seconds? Mm-hmm. Let's just count that. Okay. Okay, let's demonstrate what seven seconds is. Okay. Okay. So I will make a sound like a, I do a better chicken than goat. So, oh, sure. Okay, do you want to set the timer? Okay, okay. Okay, so I feel like I'm making the choice between goat and chicken and to make an animal sound at all.

14:18So, okay. Have we started?

14:27That was seven seconds. That was all. So that time, but in reverse, my brain had possibly already made the choice to go Bacar. Yeah. Yeah. Something in your brain was like, oh, yeah, I'm going to start setting the stage, I guess, for me to make this noise. Seven freaking seconds. John was surprised when he saw this. He was like. We really have to make sure this is correct. so we went and did all sorts of controls he saw that it was real he saw the signal seven seconds out before people said that they made the decision so there's something deep in your unconscious that seems to be preparing it's already almost as if the brain made up its mind but you don't know about it yet for me it does kind of take care of the criticism we're talking about where it's like oh maybe people are just a little bit bad or exactly when they made the decision because in seven seconds that was a long time they're not going to be that late so does john know what the blip means like what is happening in the brain when the brain is making the choice yeah what does this blip mean is it is it your brain actually deciding should i move the left finger or the right finger ahead of time right or is that signal just kind of like foreplay like parts of your brain kind of gearing up getting ready to make this decision that doesn't actually happen until later.

15:53Okay. Like, what is going on in the blip? Yes. So, yeah. So, John wanted to answer this, so they use machine learning algorithms to try to answer this question. Can they predict whether people will move their left finger or their right finger before they say they made the decision? Okay. And so, if his algorithm could predict it, that means that there is a pattern in the brain saying, push the left button, push the right button. Okay. before we are consciously aware of it. That would be, if he could predict it well. Yes. But if he couldn't predict it so well, we don't know what that blip is doing.

16:31Yeah, here's what he found. It turns out that you can make a prediction, but it's not perfect, which is quite interesting. So it was about 60 % accurate? Yeah, yeah, something around 60%. So you're tossing a coin, you're at 50%. You can predict at 60%, so a little bit above chance. What does that mean to you, Meryl? Well, I wasn't that impressed, to be honest. No. I was like 60%. That's a fart above random chance, right? Yeah, yeah, yeah. But then, so after a job study comes out, there was another group that did a similar experiment using a different technique and zooming in on this time period right before people say they made the decision.

17:12And they get it up to over 80%. Uh-huh. 80 % now. 80 %? Okay. Okay. Okay. And other studies were coming out too. Most of them all replicating the fact that like, yeah, there is something going on in the brain before people say they made a decision. And these studies end up being hugely influential. You know, John's study gets cited almost 3 ,000 times by other papers. 3 ,000 times? Close to that. Yeah. That is for the folks who are not complete nerds in the room. that is a hugely influential paper. Yeah. Okay. I don't, I don't see a paradox here though, because we still may have made the choice for that first domino to fall, right?

18:06For that first brain activity. It's just that consciousness comes a little later. I guess you're kind of getting at like, what is the me? Like, is there some part of me that can still direct some neurons around without me being aware of it. Yes, yes. Which still feels like it's really changing the idea of what free will means for most people. I would think most people would say, no, I know when I made my decision to flap my wrist. Okay, okay. It's not like some unconscious thing happening in my brain. So people, scientists believe this. They believe, what do they make of this blip? They're arguing about it.

18:40Yeah, of course. On the one side, you have people who are like, take these studies and run with them to say like, so free will is an illusion. You know, clearly all these studies, that's what they're saying. We just, you know, our decisions are kind of being made without our conscious awareness. But then there are other people, including lots of scientists, who are not convinced that these experiments mean that there is no free will. So up next, I'll tell you the most convincing argument that I could find on how free will is still totally compatible with all of this science. Coming up.

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21:22Welcome back. Today on the show, Free Will. Was I making a choice when I said that? Or that? Or that? Meryl Horne is about to tell me why I did make that choice. And I'm sorry about it as well. That's okay. I'm making the choice to forgive you. All right. So, yeah, so far we've been building up this picture where there's no free will, right? Yes. We've seen this evidence that our brains are kind of coming to decisions on their own before we're aware of it. But next we're going to hear a different story. So let me introduce you to Sean Carroll. He's a theoretical physicist and professor at Johns Hopkins University.

22:11in Baltimore. What's the best thing that you've done recently with your free will? The best thing I've done recently with my free will? I think I've really perfected my French onion soup. Is that okay? Like I really worked on this. You got to spend a lot of time caramelizing the onions. Yeah, I can never be bothered. You rush it. I just eat raw onions, basically. I mean, I haven't even attempted friends on you to say. I think I can see where your problem is. But besides cooking tips, you know, we also talked about how free will can exist alongside all the science that we've been talking about.

22:55Okay. And to me, the best way to explain this is to actually talk about something completely different. Let's talk about the weather. Weather predictions use atmospheric science, fluid mechanics. When you talk about the atmosphere around you, what do you talk about? You talk about its temperature, the pressure, the humidity, the velocity of the wind, things like that. So that's how we predict the weather. Temperature, pressure, super useful concepts. Yes. But the weird thing is, this stuff doesn't exist when we look at individual atoms and molecules that make up the weather. Like, you can't look at one little atom and see that it's 20 degrees outside.

23:40Uh-huh. Yes, a tiny little atom doesn't know what's going on in the rest of the world. You can't see these bigger, like, these bigger things. Temperature, pressure, that kind of thing. Okay. only emerges when you get a bunch of atoms together. And so, yeah, it's like you have to see how a bunch of these guys are all behaving together as a group to see certain properties. Okay. And that idea is called emergence. The idea of emergence is there are multiple ways of talking about the universe. So we distinguish between the microscopic theory, that's the lower level theory with all the atoms and things like that, And then the emergent macroscopic higher level theory where there's people and puppies and baseballs and stuff like that.

24:28Mm-hmm. Okay. So another example I like here is the ocean. Wendy, do you agree the ocean is real? Shut up. Game movie. I refuse to be trapped.

24:46Yes, the ocean is real. There are currents, there's tides. Everyone knows the ocean is real. Yes. But if you zoomed in and looked at an individual water molecule, you can't see any of that stuff. It's not like you would see a teeny tiny wave in a water molecule. Those things only exist when you get a bunch of water molecules together doing all kinds of crazy stuff. Yes. And so maybe that's how free will works too. That feeling that you are the one choosing the ice cream. It's not necessarily an illusion. It's just emergent, something that only appears at a higher level. Here's John. The you that is making that decision is a sort of collective emergent phenomenon that comes out of all of the microscopic properties and processes going on in your brain, each one of which obeys the laws of biology, if we're talking about neurons and synapses firing, etc., or the laws of physics if we're talking about the atoms and molecules.

25:48No matter what's happening in your brain with the neurons, that doesn't necessarily mean that what's happening at the higher level, this experience that we're having of making choices, it doesn't necessarily mean that that is like a fake experience or one that is like not real just because of like all the stuff happening at the lower levels. It's just like two separate levels. Oh, the ocean is real. That's what he said. The ocean is real. The ocean is real. Yeah. Okay. So where do we go from here then? Well, so this is basically what now a lot of academics think is really important for understanding stuff like free will.

26:32Because maybe you can have a system that is sort of, you know, billiard balls, like this deterministic clockwork at the lower levels. but maybe things get weird and like indeterministic at like the higher you levels, which for me is like it's still a little unsatisfying if we can't actually like, you know, know how the, you know, me choosing my ice cream emerges from like neurons zapping each other. But Sean was kind of like, well, you know, it just might take us a long time to figure out exactly how the emergent properties come about. I think there are so many examples of things that we never thought we'd be able to understand.