# Is free will real?



## amateurguy (Dec 5, 2008)

(Warning: Long thoughtful post including philosophy and science ahead!)

I've been thinking about this for quite some time already:

Let's imagine that we can freeze time and measure the position and momentum of *every single particle in the Universe*. Even the subatomic particles, especially electrons ...

Given this information, we would be able to calculate, through some physical laws, how each particle will collide with each other and where they'll be at any given time in the future. This sort of means that we can predict the future, because everything is made of matter, which is made of particles and we would know how they'd interact with each other. 

We would be able to predict a dice roll, the weather, natural disasters etc

If we calculate way ahead into the future, we would ultimately know how the Universe is gonna end. Even more, we can backtrack and see how the Universe began with altogether. 

Pretty cool? Now look at this.

Our bodies are made of particles correct? So even we humans would fall under this prediction hypothesis?

After all, cells are still made of particles and subatomic particles right? So, if we knew the information of every single particle in the Universe, we would be able to calculate how outside particles would interact with the particles in the cells and how the cells would produce stuff like enzymes (even where the enzymes would go) and, eventually, how the cell would die.

Nerve impulses? They're electricity right? Electrons. We would be able to calculate where the signals would move, how they would move, what caused them to move... Stuff like adrenaline and endorphins: they're still particles of which we would be able to calculate their motion.

So we can actually calculate the behaviour of other people... and therefore, calculate their actions and decisions.

Which leads us to the big question:

*Is there such thing as free will?*

Has everything been fated?

Are decisions real?

Are we saying that whatever that we have done, and whatever that we do, and especially whatever that we will do, has already been determined?

If so, does that make us not liable for our actions?

So, I looked up on the topic (inclining to find a disproof), and I found this question-and-answer:

Q: 
What is the scientific principle stating that the measurement of any object affects that object--that is, that it is impossible to get a perfect measurement? Who came up with this idea, and can it be tested?

A: 
You are referring to the 'Uncertainty Principle,' deduced by Werner Heisenberg early in the 20th century. Heisenberg realized that one implication of quantum physics is that the act of measurement always disturbs the object measured. The Uncertainty Principle applies to all objects, but is only significant at the atomic or subatomic level. At such scales, there are discernible limits to how certain we can be about an object's position.

The physical reason behind this uncertainty is that measurement, by its very nature, requires using some sort of energy--for example, shining a light on the object to be measured. Light consists of discrete units, or quanta, of energy known as photons. Shining a light on an electron means bombarding it with photons, each of which has a big effect on the electron.

Heisenberg and his fellow quantum pioneers recognized that very energetic photons will give a more accurate reading of the electron's position, but they are also more disruptive. Hence, there is a tradeoff: the more precisely we know an object's position at the time of measurement, the less we know about its present whereabouts. This uncertainty cannot be eliminated by designing better instruments; it is inherent in the laws of quantum physics.

One significant test of the Heisenberg principle can be thought of in philosophical terms: _Let's say we could measure both the position and velocity of every sub-atomic particle with infinite accuracy. Then we could measure the position and velocity of every particle in your body, and predict the future positions and velocities of every particle in your body. In other words, we could predict exactly what you are going to do for the indefinite future; you would have a deterministic world which precludes free will. The Uncertainty Principle is the physical reason why free will is possible. Even with infinitely accurate instruments, we cannot predict the future actions of sub-atomic particles, and therefore we cannot predict the future of macroscopic particles (like people) either._


Ok then... now I know that no matter what, I won't be able to predict what the people of the world, including me, would do tomorrow. Fair enough, but I need someone to help me explain why that still makes free will possible.

Even if we don't know what course the particles would take, they are still 'set on a course' right? 

Experts? Help! It's kind of depressing when you think about it.


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## ErikJ (Dec 5, 2008)

particle physics and human decision making are two completely different things. just because you can figure out what particles in the human body are up to doesn't mean you can predict someones actions.

work backwards...

Let's say I flail my arms randomly in the air for no apparent reason. Where did the action come from? muscles applying a force to the bones and ligaments in my arms to cause them to flail. those muscles applied that force because my brain told them to. unless you decided to stop time right at the moment when I DECIDED I wanted to flail my arms you would have no idea I what I was going to do. brain impulses are controlled by a persons thoughts which are random and unpredictable with any kind of physics. 

So sure, I guess you can predict what someone is going to do but only after they decided to do it.


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## Escher (Dec 5, 2008)

i was under the impression that on the quantum level, things ARE random and CAN happen for no reason.

but im not a particle physicist in any sense of the word.


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## Swordsman Kirby (Dec 5, 2008)

http://en.wikipedia.org/wiki/Laplace's_demon


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## Bryan (Dec 5, 2008)

Escher said:


> i was under the impression that on the quantum level, things ARE random and CAN happen for no reason.
> 
> but im not a particle physicist in any sense of the word.



Is it that they're random, or that they can't be observed without potentially changing them?


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## ImNOTnoob (Dec 5, 2008)

I understand you...
You mean everything that happens in the universe can be predicted, including human and other animal's actions, which might seem totally random, but actually, you are predestined to do it.

For example, if i could calculate, i can know i will go to the toilet in exactly 35 minutes, and 23 seconds, and will stay there for 41 seconds. 

Or that i will continuing typing this for the next minute.

This is a nice topic, maybe even we can put the calculations to good use, such as solving police cases and such..

Minutes up!


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## killswitch (Dec 5, 2008)

I suppose predictions are possible, but would probably be as accurate as current weather predictions. Assuming you could identify and analyze all the variables and data with current technology.... um.... no its not possible.

Hell, I can't predict what I am going to do in the next 5 minutes, let alone the universe.


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## nitrocan (Dec 5, 2008)

The reactions that we give against those happenings (the collision of the particles as you say) IS free will. Even if it's predictable, it doesn't mean that it's not your choice. If someone was able to predict ALL the atoms, electrons, photons and etc.'s movements and their collision with each other, then yes, he will be able to predict the future, and since every single thing triggers many other things, it's almost (probably all the way) impossible to measure every single thing and calculate the results.


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## ImNOTnoob (Dec 5, 2008)

one will need a computer with a near infinite number of space.
It will take humans many billion of years to develop such a storage device that can fit into the tiny area of earth's crust. By then, the human race will be extinct.


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## badmephisto (Dec 5, 2008)

ErikJ said:


> particle physics and human decision making are two completely different things. just because you can figure out what particles in the human body are up to doesn't mean you can predict someones actions.
> 
> work backwards...
> 
> ...



No. see, you completely miss the point. In the moment that that the big bang happened, and you could measure every particle, the claim is that everything was determined right then. Right after that bang, it was absolutely for certain that some billion years later there will be a bunch of atoms that happen to make up an organism like yourself, and there will be an electric impulse that will make you flail your arms. That decision was already made at the big bang, by the way the elementary particles expanded... by the initial conditions of the system. Now its just playing out...

We are all just a bunch of particles, but through our mind we have the capacity to be egoistic and think that there is something fundamentally different about the electrical impulses in our brains... something that does not conform to laws of physics, something like free will.

Thats the idea. I of course am materialistic enough to believe all of this, and I'm perfectly ok with it. But there are good arguments against this, for example coming from Quantum Physics and stuff.


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## Bryan (Dec 5, 2008)

ImNOTnoob said:


> one will need a computer with a near infinite number of space.
> It will take humans many billion of years to develop such a storage device that can fit into the tiny area of earth's crust. By then, the human race will be extinct.



Well, the data needs to be stored by something, and that something would be something, so it would need something to store it. So unless you can store all the data outside the universe, you can never do this.


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## shelley (Dec 5, 2008)

I took a class on the neuronal basis of consciousness a few years ago, and I remember this from one of my lectures. Measurements of neural activity have shown that neurons will begin firing signals to start an action before your brain is consciously aware of the decision to do that particular action. You may decide spontaneously to flail your arms in the air, but your neurons have already started firing signals to flail your arms fractions of a second before you decided to.

I'll try to find a link to a source when I have time. I know Leyan was in that class.. maybe he remembers that lecture too. Or maybe he was sleeping.

If we never know whether or not we truly have free will, is the illusion of free will enough for us?


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## nitrocan (Dec 5, 2008)

If people have souls (please don't tell me that's ridiculous), then you can't predict an outcome of something precisely.


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## Stefan (Dec 5, 2008)

Define *free will*, particularly the *will* part. That's crucial!

These might help, particularly the *compatibilism* parts:
http://en.wikipedia.org/wiki/Free_will
http://en.wikipedia.org/wiki/Compatibilism_and_incompatibilism


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## gogozerg (Dec 5, 2008)

The problem is not about making a computer big enough to predict the future. The question is: Does *choice* exist? We should first define this word that doesn't mean anything in physics.

Anyway, I remember long ago I asked that kind of questions to a neurologist I knew. She told me:
_"Everything we know tends to prove the human or animal brain is nothing more than a purely deterministic machine. One day, we'll be able to reproduce this mechanism and create perfectly normal human beings. No such thing as 'free will' in science. Come on, are you retarded? It's like asking whether god exists or not!"_

Every concepts that make us feel human (having a soul, feelings, choice), are mainly poetry.



amateurguy said:


> Help! It's kind of depressing when you think about it.


Welcome to the world of philosophy, a place where it's risky to dare to say _"I"_. If you prefer the blue pill, there's still religion to save your soul.


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## nitrocan (Dec 5, 2008)

Just go to www.philosophyforums.com or something (Warning: Danger of losing your mentality lol  just kidding)


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## qqwref (Dec 5, 2008)

One of the important and interesting results of quantum theory is that particles don't have a definite momentum, energy, etc. It's more than just being uncertain if measured: if you actually take a measurement, what you get ends up being determined by probability. You might have, say, 1/2 chance of finding the energy of a particle to be a certain value E, and 1/2 chance of finding it to be 2E (because the particle is in what's called a 'superposition' of the two states).

One really bizarre result related to this is the so-called "double slit experiment". If you have a wall with two slits at it, and a piece of photographic film on the other side, and you fire large numbers of photons at the wall, they will interfere with each other and make a diffraction pattern. That makes sense, since sound waves will diffract too. But if you fire ONE photon at a time... you STILL get a diffraction pattern! It is almost as if the photon is going through both slits and interacting with itself: even when you shoot the photon at one slit, in the same direction every time, it still hits the film at many different areas. So there's no way you could keep track of all the positions of each particle, because just trying to measure the exact position of one particle is an extremely difficult task, and the outcome is determined by probability anyway.

Incidentally, if you actually knew all the data about every particle, it would be a ridiculously huge amount of information. There are something like 600 (!!!) bits of information for each particle to store position alone (in a universe which is 13 billion light years across and where the Planck length is the smallest discrete step of length). If you didn't store this efficiently you'd easily need more than the number of particles in the universe to keep all this. I have a feeling that it would be impossible to store this much data without using all of the matter in the universe to do it, although I can't prove this. But this isn't something we could ever be technically capable of.


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## Dene (Dec 5, 2008)

I love the huge post that can be summed up in one word. (Determinism).
Personally, I reject determinism. I think current quantum theory says that at the fundamental level, particle movements can be completely random.

Shelley: That is correct: there were experminets done showing that the brain makes the decision before you are consciously aware of it.
One experiment had a clock hand going around a circle at a certain speed, and a person was asked, just completely randomly, to spontaneously stop the hand whenever. They were not meant to plan it, or think about it, but just do it spontaneously. The experimenters found that they could locate actions in the brain, before the person was aware of their choice. Literally, only milliseconds before.


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## Tox|k (Dec 5, 2008)

To have absolute determinism you'd need to be able to perfectly predict every action and reaction of the most discrete elements of a system, and as far as we know, this is on the level of sub atomic particles. Unfortunently there are issues that arise when we try to do this. One is that we can never know the exact position and momentum of a particle (due to the uncertainty principle). The other, is that the best theory we have for prediciting interactions on the particle level is quantum mechanics, and it is inherently probabilistic.

Einstein has been quoted saying "god does not play dice" which exemplifies his dislike of the probabilistic nature of our universe. He was never satisfied with the fact that we can never perfectly predict the outcome of a quantum system, and, spent a great number of years trying to figure it out. He wasn't the only one either, many of the founders of quantum mechanics were unsatisfied with it's probabilistic nature. Now a days such philosphical debates of quantum mechanics have taken a back seat. Physists have realized that the best way to make headway with quantum mechanics, is to do the math 

sidenote:
There is more to the uncertainty principle that it's simple position/momentum duality; it also has implications for energy and time. And it also manifests itself very distinctly mathematically as well. It's actually kind of ironic that we can never know the exact position and momentum of a particle, but we can know precisely how much we may be off. Quantum mechanics also does much stranger things thank just uncertainty, such as superposition, which qqwref alluded his very informative post.


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## Stefan (Dec 5, 2008)

Tox|k said:


> To have absolute determinism you'd need to be able to perfectly predict [...]


Nope. Determinism is not about predicting.


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## EmersonHerrmann (Dec 5, 2008)

I'm just waiting for Lucas to pop in and do some crazy calculations that prove either side of this argument xD Really good thread, but I like to believe in fate...all particles have a fate, hence we have a fate


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## fanwuq (Dec 5, 2008)

We were just studying transcendentalism in English class. One thing we read was "Fate" by Ralph Waldo Emerson.



Emerson said:


> If you please to plant yourself on the side of Fate, and say, Fate is all; then we say, a part of Fate is the freedom of man. Forever wells up the impulse of choosing and acting in the soul. Intellect annuls Fate. So far as a man thinks, he is free.



I think fate is only a limitation that you replace one yourself. Whether it is truly real or not, live as if you have full free will.

This is a much better thread for my random questions than the religion thread.  That thread got too agressive and I can see that other than Michael Gottlieb is giving interesting answers, most people ignore the questions by insulting them.


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