I don't believe in free will. This is why.

Summary

The script delves into the concept of free will, arguing that it doesn't exist due to the deterministic nature of physics and quantum mechanics' inherent randomness. It explains that human behavior is governed by the same physical laws that dictate particle interactions, suggesting that decisions are not freely made but are a result of deterministic brain functions with occasional quantum randomness. The speaker, a physicist, critiques the notion that free will is necessary for addressing climate change, emphasizing the importance of understanding human cognition and societal structures instead. The script also touches on the philosophical debate surrounding free will, introducing compatibilism and libertarianism, and concludes with the speaker's stance on 'hard incompatibilism'.

Takeaways

• 🧐 The universe is governed by a combination of deterministic and random quantum physics, which questions the concept of free will.
• 🤔 The standard model of particle physics describes all known particles, which collectively make up humans and their behaviors.
• 🚫 Despite knowing the equations for human behavior, we cannot practically solve them due to the vast number of particles involved.
• 🔬 Quantum mechanics introduces an element of randomness through quantum jumps, which are unpredictable and uncontrollable.
• 🌌 Emergent properties arise from the interactions of particles, but they do not override the underlying physical laws.
• ⚖️ Philosophers have debated the nature of free will, with some arguing for compatibilism (free will is compatible with determinism and indeterminism).
• 🚫 The speaker, a physicist, leans towards hard incompatibilism, concluding that free will does not exist within the framework of known physical laws.
• 💡 Free will is sometimes redefined by philosophers to mean decisions that are largely independent from external factors and driven by internal deliberation.
• 🧠 Neuroscientists focus on whether decisions are made consciously or unconsciously, which is distinct from the philosophical debate on free will.
• 🌱 Quantum fluctuations in the early universe may have played a role in shaping the world, but the details were not determined at the Big Bang.
• 🌍 The belief in free will can lead to misguided approaches to societal problems, like climate change, by overestimating individual control and willpower.
• 📚 Understanding the physics behind decision-making and societal structures can lead to more effective strategies for addressing complex issues.

Q & A

What is the speaker's stance on the existence of free will?

The speaker believes that free will does not exist, aligning with the philosophical position known as 'hard incompatibilism'.

What is the standard model of particle physics, and how does it relate to human behavior?

The standard model of particle physics is a theory that describes the fundamental particles and forces that make up the universe. It implies that human behavior is also described by the mathematics of this model, although it is practically impossible to solve the equations for the vast number of particles that constitute a human.

How does the concept of determinism in physics affect the discussion on free will?

Determinism in physics suggests that if you know the properties and motions of particles at one time, you can calculate what happens at any later time. This deterministic nature of physics, combined with the random quantum jumps, implies that our actions and decisions may not be freely chosen but are instead determined by the laws of physics and random quantum events.

What is an 'emergent property' and why is it relevant to the discussion on free will?

Emergent properties are behaviors or properties that arise from the interactions of a system's components, which do not exist at the level of the individual components. In the context of free will, the idea is that while human decisions may be emergent properties of the brain's complex interactions, they are still governed by the underlying physical laws and not by a separate entity called 'free will'.

What is the 'Free Will Theorem' and what does it suggest about human and particle free will?

The 'Free Will Theorem' is a mathematical theorem proved by John Conway and Simon Kochen. It states that if humans have free will, then elementary particles also have free will, and vice versa. However, the speaker argues that this theorem does not provide evidence for the existence of free will, as it is based on the assumption that particles could have free will, which is not a widely accepted idea.

What is the difference between 'compatibilism' and 'libertarianism' in the context of free will?

Compatibilism is the philosophical view that free will is compatible with determinism and indeterminism, as understood by the laws of nature. Most contemporary philosophers are compatibilists. Libertarianism, on the other hand, asserts that free will exists and is incompatible with determinism. It often involves the belief in non-physical aspects of free will or the rejection of established science to accommodate free will.

How does the speaker address the misconception that the absence of free will implies a lack of personal responsibility?

The speaker argues that the absence of free will does not imply a lack of personal responsibility. They suggest that understanding the deterministic and indeterministic nature of the universe can help us make better decisions and take responsibility for our actions within the framework of our cognitive abilities and societal structures.

What is the speaker's view on the relevance of free will to addressing climate change?

The speaker criticizes the notion that believing in free will is necessary for addressing climate change. They argue that the belief in free will can lead to unrealistic expectations about individual willpower and can misdirect the focus from systemic and collective solutions to the climate crisis.

How does the speaker explain the illusion of free will in decision-making?

The speaker uses the idea from Wittgenstein that we cannot know the result of a calculation our brain performs before we complete it, which gives us the impression that our decisions are 'free' until we reach a conclusion. However, these decisions ultimately follow from deterministic brain functions and occasional random elements.

What is the speaker's perspective on the role of quantum mechanics in the debate about free will?

While acknowledging the random quantum jumps as part of quantum mechanics, the speaker does not believe that these random events provide a basis for free will. They argue that attributing free will to particles based on their indeterministic behavior is not a valid argument and does not translate to human free will.

What does the speaker suggest about the impact of the belief in free will on societal issues?

The speaker suggests that the belief in free will can lead to misplaced blame on individuals for societal problems, such as climate change. They argue that understanding the limits of human cognition and the deterministic nature of the universe can help in addressing societal issues more effectively through collective action and systemic change.

Outlines

00:00

🔬 Physics and Determinism in the Universe

The script begins by discussing the deterministic nature of the universe as described by physics, with the exception of random quantum jumps. It questions the concept of free will, suggesting that it is an illusion and not a topic of interest. The speaker argues that human decisions are governed by the standard model of particle physics, which is deterministic, and that although quantum mechanics introduces randomness, it does not equate to free will. The paragraph emphasizes the complexity of human behavior as an emergent property from the interactions of fundamental particles, which are beyond our computational ability to predict but are still deterministic in nature.

05:05

🌌 Emergence and the Illusion of Free Will

This paragraph delves into the concept of emergent properties in the universe, explaining how simple particles can combine to form complex entities with new behaviors not inherent in the individual particles. It uses the example of metals to illustrate how emergent properties like conductivity arise from collective interactions. The script argues against the notion of 'strong emergence,' where large systems might exhibit behaviors not dictated by the laws of their constituents, stating that there is no empirical evidence for this. It then ties this discussion back to the concept of free will, suggesting that the unpredictability of human decisions does not equate to free will but is a result of complex, emergent behavior.

10:08

🤔 Philosophical Perspectives on Free Will

The speaker explores various philosophical viewpoints on free will, contrasting compatibilism, which holds that free will is compatible with determinism and indeterminism, with libertarianism, which asserts that free will exists despite these factors. The paragraph discusses how contemporary philosophers like Daniel Dennett and Jennan Ismael view free will as arising from the autonomy of our brains from environmental factors. It also addresses the 'Free Will Theorem' and the idea that if humans have free will, then elementary particles do as well, leading to the conclusion that the concept of free will may be misguided.

15:11

📚 Redefining Free Will and Its Implications

In this paragraph, the speaker identifies as a 'hard incompatibilist,' believing that free will is incompatible with both determinism and indeterminism, and thus does not exist. They differentiate their stance from 'libertarian' views, which often invoke nonphysical or miraculous explanations for free will. The speaker also addresses misconceptions about the implications of lacking free will, emphasizing that it does not negate the ability to make decisions or the importance of understanding the brain's processes. They critique the belief that 'will' alone can solve complex issues like climate change, arguing that societal structures and cognitive abilities must be considered.

🌐 Quantum Fluctuations and the Illusion of Control

The final paragraph discusses the role of quantum fluctuations in the early universe as a contributing factor to the current state of the universe, suggesting that details of the universe were not predetermined at the Big Bang. It argues against the idea that the speaker's actions, such as creating the video, were caused by the Big Bang, highlighting the role of quantum events in shaping reality. The speaker also promotes understanding the deterministic nature of physics, through resources like Brilliant.org, to better comprehend the world and make informed decisions, concluding with a promotion for further learning on related topics.

Keywords

💡Free will

Free will refers to the power of making choices that are neither determined by natural causality nor random chance, suggesting that individuals have control over their actions. In the video, the concept of free will is central to the discussion, with the speaker arguing that free will does not exist due to the deterministic nature of physics and the random elements of quantum mechanics. The video explores the implications of this idea, suggesting that decisions are made through deterministic brain functions with occasional random elements, rather than a separate entity called free will.

💡Determinism

Determinism is the philosophical doctrine that all events, including moral choices, are determined completely by previously existing causes. The video script discusses determinism in the context of the standard model of particle physics, where the behavior of particles is predictable based on their properties and motions at a given time. This deterministic nature is contrasted with the random quantum jumps, leading to the argument that human behavior, and thus decisions, are ultimately determined by these physical laws.

💡Quantum mechanics

Quantum mechanics is a fundamental theory in physics that describes the physical properties of nature at the scale of atoms and subatomic particles. The script mentions quantum mechanics to explain the concept of indeterminism, where certain events, such as quantum jumps, occur randomly and cannot be predicted. This randomness is used to argue against the existence of free will, as it implies that even if decisions are not determined, they are also not freely chosen but rather the result of random occurrences.

💡Standard model

The standard model is a theory in particle physics that describes three of the four known fundamental forces (the electromagnetic, weak, and strong interactions), and classifies all known elementary particles. The video uses the standard model to illustrate that all particles, and by extension humans, are subject to deterministic laws, which are part of the argument against the existence of free will.

💡Wave-function

In quantum mechanics, a wave-function is a mathematical description of the quantum state of an object. The script refers to wave-functions to explain how particles are described in quantum mechanics and how they change deterministically over time, with the exception of random quantum jumps. This deterministic change is used to argue for the absence of free will, as it suggests that the future state of a system is fixed by its past state.

💡Emergent properties

Emergent properties are characteristics of a system that arise from the interaction of its parts and are not easily predictable from the properties of the individual components. The video explains that emergent properties, such as conductivity in metals, do not exist at the level of individual particles but arise from the collective behavior of many particles. This concept is used to argue that while human behavior may be complex and emergent, it is still governed by the underlying physical laws, which do not support the existence of free will.

💡Compatibilism

Compatibilism is a philosophical thesis that free will and determinism are compatible, meaning that events could be determined, but still, agents could have free will. The script discusses compatibilism as the view held by many contemporary philosophers who believe that human decisions are largely independent from external factors and are driven by internal deliberation, suggesting that free will can coexist with the deterministic laws of nature.

💡Libertarianism

In the context of the video, libertarianism refers to a philosophical stance on free will that asserts that it is incompatible with determinism and that agents have the power to act otherwise than they do. The video contrasts this with the speaker's own position, which is that free will does not exist because the world is governed by a mixture of determinism and indeterminism.

💡Hard incompatibilism

Hard incompatibilism, also known as 'hard determinism,' is the view that free will does not exist because determinism is true and indeterminism is also incompatible with free will. The speaker identifies with this position, arguing that since the world is governed by both deterministic and indeterministic laws, free will cannot exist.

💡Quantum fluctuations

Quantum fluctuations refer to temporary changes in energy in a point in space, which can lead to the creation of particle-antiparticle pairs in certain conditions. The video mentions quantum fluctuations to explain that the structures in the universe, including life on Earth, were created by such fluctuations in the early universe. This is used to argue against the idea that the Big Bang determined everything that has happened since, including the speaker's decision to make the video.

💡Cognitive ability

Cognitive ability refers to the mental capacity to process information, such as memory, perception, and reasoning. The script discusses the limits of human cognitive ability to highlight that the belief in free will can lead to an overestimation of the control individuals have over their decisions. This is relevant to the broader societal issues, such as climate change, where the video argues that the problem lies in the organization of society rather than in individual willpower.

Highlights

The future is determined by the past and random quantum jumps, which are uncontrollable.

Free will is often questioned, but the speaker finds the concept uninteresting and believes it doesn't exist.

Decision-making and its relation to the Big Bang are discussed, suggesting a deterministic universe with random quantum events.

The standard model of particle physics is introduced, describing the fundamental particles and their stability.

The behavior of particles is deterministic, with the exception of random quantum jumps during measurements.

Wave-functions in quantum mechanics imply uncertainty in properties like position and momentum.

Gravity adds to the determinism of the universe, but does not change the underlying deterministic nature.

Emergent properties arise from the interactions of particles, not from the particles themselves.

The concept of 'decoupling of scales' allows for understanding large-scale phenomena without delving into small-scale details.

Compatibilism is presented as the philosophy that free will is compatible with the laws of nature, including determinism and indeterminism.

The Free Will Theorem suggests that if humans have free will, then elementary particles also possess it.

Contemporary philosophers redefine free will as decisions being largely independent from external factors.

Daniel Dennett and Jennan Ismael's views on free will are discussed, emphasizing autonomy and internal deliberation.

Libertarianism is presented as a philosophy that supports free will, with various interpretations including quantum randomness and nonphysical aspects.

The speaker identifies as a 'hard incompatibilist', arguing that free will is incompatible with both determinism and indeterminism.

The idea that free will doesn't exist doesn't negate the ability to make decisions; it simply means decisions follow from deterministic brain functions and random elements.

The role of quantum fluctuations in the early universe and their impact on the current state of the world is discussed.

The belief in free will can lead to unrealistic expectations and blame on individuals rather than societal structures.

The importance of understanding the deterministic nature of physics for making informed decisions and addressing societal issues like climate change.

Transcripts

The future is determined by the past, except  for random quantum jumps which no one can  

control. Causes have causes have causes, and  they go back all the way to the Big Bang.  

Does that mean we have no free will? People  often ask me that. I find the question stunningly  

uninteresting. Of course we don’t have free  will. Ok, then, how do we make decisions? Do  

we make decisions? Did the Big Bang make me do  this video? That’s what we’ll talk about today.

I already made a video about free will a  few years ago. But I’ve noticed recently  

that a lot of people think free will is  relevant for addressing climate change.  

And because I don’t believe in free  will I’ve suddenly become a problem.  

This is complete nonsense. But  let’s start at the beginning.

And we begin of course with physics. Everything  in the universe is made of 25 particles that,  

for all we currently know, are not themselves  made of any smaller constituents. We collect  

them in what’s called the standard model  of particle physics. That’s everything  

in the universe, except possibly dark  matter, but that’s a different story.

Most of those particles are unstable and  decay very quickly. How can it be that  

a particle which isn’t made of anything can  decay? That’s a question I get so frequently,  

I made a video about that specifically.

For now, let’s stick with the particles that are  stable. Those are the ones that we are made of,  

electrons, up and down quarks,  and photons and gluons to hold  

them together. And good thing they’re  stable because otherwise you’d be more  

radiant than a nuclear fuel rod.  You’d also be dead very quickly.

Ok, so humans are one big collection of  particles. What the particles do is described  

by the mathematics of the standard model. It’s  a lot of maths, and you need that maths if you  

want to answer difficult questions like what’s  going on in LHC collisions. For simple questions,  

like whether free will exists, we don’t need to  know much about the maths. Relevant is just that,  

ultimately, what you and I do is  also described by the standard model.

And yes, that means that we know  the equations for human behaviour.  

We can write them down. In practice,  that’s a completely useless statement,  

because we can’t solve the equations for  all these 10 to the 30 or so particles that  

humans are made of. Not even the biggest  supercomputer in the world could do that.

But we don’t need to solve the equations to  draw conclusions from their properties. For the  

purposes of this video, the most relevant property  of these equations is that they are deterministic,  

which means that if you know the properties  and motions of the particles at one time,  

you can calculate what happens at any later time. Ok, it isn’t quite as simple. Because this is  

quantum physics, so on top of this deterministic  behaviour, there’s an occasional quantum jump  

which happens randomly whenever you make  a measurement. Y’all know that I don’t  

believe this stuff with the quantum jumps.  But today I’ll stick with the most generally  

accepted theory. So, we have particles that  behave deterministically plus random jumps.

In quantum mechanics we use wave-functions to  describe the particles, and this implies that  

there are some quantities, like position  and momentum, whose values you can’t know  

precisely at the same time. But the wave-function  still changes deterministically. If you want,  

you can include gravity, but that is just a  deterministic theory. A non-quantum theory,  

or a “classical” theory as physicists say. So,  gravity just adds some more determinism on top.

And that’s how the universe works,  for all we currently know. It’s one  

big wave-function that contains all  those particles. Its change in time  

is deterministic with the occasional random  jump. The deterministic part is fixed by the  

past. The random jumps cannot be influenced  by anything because that’s what it means for  

them to be random. And that’s it. Please don’t  blame me for this. I swear it wasn’t my idea.

Physics is great, but it doesn’t tell you much  about human anatomy, other than possibly that  

flapping your arms won’t make you fly. That’s  because if you combine many particles, then  

things get very complicated very quickly. You get  new, “emergent” behaviour as it’s often called.

You don’t even need to look at difficult things  like human beings to see that. If you do as much  

as combine atoms to big chunks called metals  you get new behaviour, like the ability to  

conduct electricity. Or being very shiny. Or  being very painful if they fall on your foot. 

Emergent properties don’t exist  on the level of the constituents,  

they arise from the properties and  interactions of the constitution. A  

single electron doesn’t have a conductivity.  That just doesn’t make sense. Conductivity  

is a property that only makes sense  for large collections of electrons.

It doesn’t make sense to talk about the  conductivity of an electron for the same  

reason it doesn’t make sense to ask whether  a single oxygen atom is a gas, or what’s the  

marital status of your small intestine. It’s  what philosophers call a “category error”. It’d  

be trying to assign a property to a class to  which it doesn’t belong. Emergent properties  

don’t make sense on the underlying levels. But  that doesn’t mean they don’t exist. Chairs exist,  

alright, but they exist on the macroscopic level,  and not on the level of elementary particles.

Curiously enough, our universe is organized  so that the details of what happens at short  

distances become less important at large  distances. This is why, if you want to  

understand planetary motion you don’t need to  know the population of New York City. This is why,  

if you want to understand chemical reactions you  don’t need to know the standard model of particle  

physics. And this is why, if you want to become  a YouTuber, you don’t need to know anything.

Physicists call it the “decoupling of  scales”, the mysterious but empirically  

well-confirmed fact that the details  of what goes on small scales can be  

disregarded if you’re only interested  in what happens on large scales. And  

this is why we have so many disciplines  of science. Because each discipline of  

science has its own language about emergent  properties that are adequate to its subject.

But that we get new, emergent, properties  from the interactions of the constituents,  

doesn’t mean the equations that determine  the behaviour of the constituents no longer  

apply. Emergent behaviour is a consequence  of combining large numbers of particles with  

complicated interactions. It *follows from the  underlying laws, it doesn’t make them go away. 

Some philosophers have speculated that large  systems could have emergent behaviours which  

*don’t follow from the laws of the  constituents. This is sometimes  

called “strong emergence”. But there is no  evidence this happens in the real world.

Though there are some mathematical  examples. If you have an infinite  

number of constituents or an infinite  number of properties of the constituents,  

or anything else being actually infinite,  there are cases where it becomes impossible  

to calculate one or the other quantity of the  entire system. A few examples for this have  

been constructed in the literature. Usually, the  proof works by a map to the halting problems or  

similar examples of computational complexity.  However, those are mathematical constructions  

that have no real-world counterpart because in  the real world nothing is ever truly infinite.

Ok, so emergent properties are an interesting  consequence of the underlying laws, but we’re  

still governed by a mix of determinism and  indeterminism. What does this mean for free will?

Free will is often described as the  possibility that one could have done  

otherwise. But this description stopped  being useful with quantum mechanics,  

because it’d mean that single  particles also have free will.

If you take for example a photon, a single quantum  of light, and you send it through a beam splitter,  

then there’s a 50 percent chance the  photon goes left and 50 percent chance  

the photon goes right. If you measure  the photon on the left you can say, well,  

it could have done otherwise. It could have gone  right, right? Does that mean it has free will?  

Well, I’d say that’s not what  normal people would call free will,  

though some physicists actually believe that  photons are observers. One of the consequences  

of that is that they’ve concluded reality doesn’t  exist. I talked about this in an earlier video.

This is also what happens in the “Free Will  Theorem”. This theorem was mathematically  

proved by John Conway and Simon Kochen in  2006. It says that if humans have free will,  

then elementary particles also have free will.  But the statement of the theorem is logically  

equivalent to the statement, “If particles do  not have free will, then neither have humans.”  

I don’t know about you, but to  me it seems reasonable to assume  

that particles do not have free  will. And either way you put it,  

the free will theorem says nothing about the  existence of free will in the first place.

So let’s return to the question of what we mean  by free will. We have seen that the idea that you  

could have done otherwise or that your actions  were not determined is not descriptive because  

of this random element from quantum mechanics.  Contemporary philosophers have therefore tried to  

capture the essence of free will in the idea  that human decisions are to a large extent  

independent from external factors, and instead  dominantly driven by internal deliberation.

Different philosophers have put  somewhat different spins on this  

story. But it always comes down to the  idea that human decisions are difficult,  

if not impossible, to predict from  external input and observations alone.

The philosopher Daniel Dennett for example  captures the essence of free will in our  

“ability to see probable futures – futures  that seem like they’re going to happen” and  

then the possibility to take steps that  something else happens instead, like,  

for example an autonomous vehicle does.  The philosopher Jennan Ismael has even  

written a book called “How Physics Makes Us  Free”. She basically says that free will lies  

in the large degree of autonomy that our brain  has from environmental factors as it operates.

Those are typical examples of  what is called “compatibilism”,  

that’s the philosophy that free will is  compatible with the laws of nature as they are,  

a mixture of determinism and indeterminism. Most  contemporary philosophers are compatibilists.  

According to a 2020 survey, almost 60  percent. But it’s not like this is a new idea,  

well known philosophers like David Hume  and John Stuart Mill were compatibilists.

The other big camp is that of libertarianism,  whose supporters also believe in free will.  

Their philosophy comes in several variants.  First, there are those who insist that  

the randomness of quantum mechanics  makes place for free will. As I said,  

I don’t see how this makes sense. Then there  are those who acknowledge that an element of  

indeterminism doesn’t entail free will, but  who then throw out some established science to  

make place for miracles. Like for example the  ability to change the past by your thoughts.

And then there are those who just insist that free  will exists but it’s nonphysical. The latter is  

a well-trodden road. For example, Rene Descartes  and Immanuel Kant were both in that camp. I’d say  

the idea is not wrong, but I never understood  what the point is. Because if free will is not  

physical it doesn’t explain anything in the  physical world, so why bother inventing it?

I am in neither of those camps. The science  writer John Horgan once called me a “free  

will denier”. I think that’s a misunderstanding.  It’s not that I’m denying people feel like they  

have free will. But I’m with libertarians  in that I think free will is incompatible  

with determinism. I also think it’s  incompatible with indeterminism. And  

since the real world is governed by a mixture  of determinism and indeterminism, I arrive at  

the conclusion that free will doesn’t exist.  It’s sometimes called “hard incompatibilism”.

The good thing about hard incompatibilism is that  

you don’t need to explain what free will  is in any detail. You just need to say:  

whatever it is, it isn’t compatible with  what we know about the laws of nature.

That said, I don’t have a problem  with compatibilism. If you want  

to define whatever as free will, please go ahead,  

it’s just a definition after all. If your  definition leads you to the conclusion that  

photons also have free will I’d find that a  tad bit ridiculous but maybe that’s just me. 

I should add that when neurologist discuss  the question of free will they talk about  

something else entirely. They are concerned  with the question whether we make decisions  

consciously or unconsciously. Interesting  question, but not what I’m talking about today

I recently gave an interview and the guy  said to me if free will doesn’t exist,  

why don’t I kill myself tomorrow because what’s  the point of anything. This isn’t a joke,  

it actually happened. It wasn’t even the first  time people said something like this to me.  

And I’m afraid it won’t be the last time. Which  is why I’m here talking about free will again.

I’m not a psychologist. I’m a physicist.  I don’t know what to say to people who  

have existential angst other than,  please see a psychologist. I’m not  

a philosopher either. For what I am  concerned, if free will doesn’t exist,  

it’s never existed, so what difference  could it possibly make for your life.

I believe the problem is that many of  us have grown up thinking our brain  

works in a particular way. Then we learn  that this isn’t compatible with science,  

and we have a hard time readjusting  how we think about ourselves.

The free will story suggests that the brain  works like this. You use your neural circuits  

to consider different options, for example, what  you could eat for lunch. You draw on your memory,  

and the associations you have for each  possible option, and try to imagine how  

much you would enjoy it. Then you take this  thing called “free will” and use it to pick one.  

The challenge is now to integrate  the knowledge that the thing you  

call free will is just another part of this  algorithm that runs in your neural circuits.

A good way I’ve found to make sense of this goes  back to Wittgenstein. We can’t know the result  

of a calculation that our brain performs before  we have completed the calculation. If we did,  

we wouldn’t have to do the calculation.  This is why we have the impression that the  

decision is “free” until we’ve arrived at the  conclusion. But the result ultimately follows  

from deterministic brain functions,  with the occasional random element.

If that sounds weird, all it means is  that our decisions follow from what we  

want. And I think that’s a good thing. I’d  find it creepy if there was something else,  

call it free will or whatever, that  would affect the decisions in my brain. 

So that you don’t have free will doesn’t  mean you don’t make decisions. Of course,  

you make decisions. You decided to watch this  video, didn’t you? Good choice by the way.

Did the Big Bang made me do this video?  

No. That’s because all those structures in the  universe, including this planet and life on it,  

were created by quantum fluctuations in the  plasma in the early universe. Their details  

were not determined at the Big Bang, if there  was a Big Bang. It’s also extremely likely that  

one or the other quantum event played a role for  the world becoming just exactly as it is today.

Why does it matter? It matters because  to come to good decisions we need to  

understand how our own brain works, and how  society works overall. And the idea of free  

will suggests an inaccurate description  of reality. It makes people believe they  

have more control over what goes on  in their head than is really the case.

Fact is that our brains will process input  whether we want that or not. Once it’s in,  

we can’t get it out. This is why trauma is so hard  to cope with. This is why misinformation is so  

hard to combat. This is why what the FIFA called  “three victorious hands around a soccer ball”  

will forever look like a facepalm once someone  told you it does. You can’t “unsee” something.

And this is also why I take issue with upbeat  climate change activists, who attack realists  

as “doomers” because they believe we just  need the “will” to take action. The idea  

that “will” is all we need has led to utopian  plans for staggering amounts of carbon capture,  

home insulation and renovation, upgrades  of the electric grid, energy storage,  

and a hydrogen economy, all of which is  somehow magically supposed to pop out  

of nowhere if we just have the “will”.  This belief in free will puts the blame  

on individuals when really the problem is  the way that we’ve organized our societies.

I’d say it isn’t me who is a problem for  action on climate change, it’s people who  

disregard the limits of human cognitive  ability. I have a chapter about free will  

in my book “Existential Physics” where I also  discuss the question of moral responsibility,  

so if you want to know more, go check this out.

The reason why the laws of physics are  deterministic, plus that random element,  

is that they are based on differential  equations. If you want to know more  

about how they work, there’s a great course  about differential equations on Brilliant. 

Brilliant.org offers courses on a large variety  of topics in science and mathematics. It’s a  

fresh and new approach to learning with  interactive visualizations and follow-up  

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Thanks for watching, see you next week.