Does "Free Will" exist?

〜let's prove that we are completely free by quantum physics〜

Do you believe in the existence of "free will"?

"Free will" is a curious topic that is well-discussed in the field of philosophy, but is also relevant to fields such as physics and neuroscience.

Let's suppose that, on your day off, you wake up in the morning, and ask yourself, "what am I going to do today?".

You might think, "It's such a nice day. I might just go for walk. Well, maybe I'd rather go to a bookstore to find something to read. It may also be a good idea to go hang out with my friend, because I haven't seen him for a while."

Many of us are making these kinds of choices everyday without questioning.

We also believe that we are choosing which one of these options to actually put into action, on our free will.

But are we really making choices on our free will? This is what I would like to question today.

Questioning "Free Will"

You might say, "I am always choosing what I put into action. Therefore, free will DO exists, and that's it".

Well, let's use our imagination. Suppose that you have an enemy you have to knock down.

He is sitting on the ground, about 100 meters ahead of you.

You look around and you find a cannon with a perfect size.

Given this information and some basic mathematical knowledge, you can calculate the angle and the speed where you should fire the cannon to hit him.

(I know it is not so simple because there are effects of other factors such as airflows and frictions, which are dependent on the shape of the cannon ball, and Coriolis force, but this is just an example, so please forgive me for being so simplistic.)

What I want to say is that "our future is calculable based on our current conditions".

It seems that causality governs every aspect of our life: when you drop something fragile on the ground, it breaks; and when you dry your hair using a hair dryer, your hair gets dry.

When we assume that the causality applies to everything, we might arrive at a conclusion that our future is completely predictable by making calculations on everything.

What if our future is completely predictable?

If so, everything, including what you'll do next, can also be said to be calculable.

In other words, it's possible to think that our entire future, that is, having a thought about what we'll do today, coming up with the options of reading a book and going for walk, and deciding to go for walk, can be said to be completely predictable.

If you think that way, the existence of "free will", which is usually accepted without any doubt, may be just a fantasy we invented in our head, because our deeds would be merely following the predetermined paths, according to the logic I described above.

Preparatory Introduction

I have just briefly explained how we can question the existence of "free will".

What did you think? Did you feel somewhat uncomfortable, thinking about the possibility of non-existence of "free will"?

Let's get into the point. I, Fully Hatter, will prove that "free will" does exist, for those of you who totally lost hopes in your life on the Earth.

The key concept here is "quantum", which is a concept in physics.

To simply put, "quantum" is something of a microscopic world.

You might have heard that any matter in this world is made of very small particles called "atoms". The main players in the quantum world are microscopic particles like atoms.

Although our world is made of these small particles, their behaviors are so strange that not only they are against our intuition, but also even experts have not understood their behaviors (although they can make predictions).

For example, in the quantum world, every quantum particle behaves as a "particle" and a "wave" at the same time. Although a "quantum" is obviously a particle (the smallest possible discrete unit of matter), but also has wave-like properties, e.g., it spreads concentrically, and forms interference fringes.

As another example, (though I know I might sound totally out of my mind,) a quantum can penetrate an infinite potential barrier, which is absolutely non-penetrable (this phenomenon is called "quantum tunneling").

Although I can't explain every strange property of these particles, I am going to introduce you some of them, particularly those pertinent to "free will."

Quantum World: "Quantum Superposition"

One of the most important quantum properties in this context is "quantum superposition".

The small particles in the quantum world can take one of two states.

We often use an analogy of a coin, which has two states of the head and the tail.

To our surprise, these quantum particles are capable of maintaining two of these states at the same time, e.g., being the head 50% and being the tail 50% (this state is called "quantum superposition").

This is completely different from the situation when you flip a coin and keep it hidden under your hand, in the world of our classic physics.

(Intuitively speaking, both of these situations may appear to be essentially the same, because the probabilities of the coin resting heads up are both 50%, but they are completely different.)

For example, assume that you removed your hand and the coin was sitting heads up. Under assumptions of the classic physics, even if you somehow managed to go back in time to immediately before you remove your hand, the result would remain the same. However, if you went back in time in the quantum world, the result could change to tails up.

Let's consider another example. Suppose that your coin has a white color on the head side, and has a black color on the tail side. If you toss the coin, the result can only be either white or black. However, in the quantum world, the coin remains "gray" until we make a measurement of the result. (There are many more differences between these worlds, including "negative probability", which we cannot intuitively understand.)

Quantum World: "Uncertainty Principle"

Another one of the important quantum properties is "uncertainty principle".

We believe that anything you can touch is measurable. We are not only able to count the number of clothes you have in your closet, to calculate the weight of your watch in grams and the speed of a bullet train in kilometers per hour, but also even to calculate the weight of the Earth.

However, it is actually impossible to make accurate measurements of small particles called atoms, which all these "matters", such as our clothes and your watch, are made of.

In order to measure the weight of a substance, you have to put it on a scale, for example. In order to examine its color, you need to irradiate it with light.

Usually, because you can't destroy objects by measuring their weight or irradiating them with light, we have been taking such approaches to make measurements without questioning, but it is a completely different story in the quantum world.

Atoms, which are one example of quantum particles, are so small and so light that their states become modified merely by irradiating them with light, however small the energy of the light is.

Through extremely precise mathematical descriptions, it has been proven that it is impossible, in principle, to make measurements of such small particles.

The fundamental constituents making up our beings are, in principle, not measurable.


You may then ask me, "How does that quantum thing have anything to do with the free will?"

If you have a good intuition, you may have realized that some of our preconditions have already been refuted, before we get into a serious discussion of the "free will".

To begin with, our deterministic idea that we are destined to a particular future is "quantumly" wrong, in the following two senses:

First of all, the behaviors of quantum elements, which are our constituents, are completely probabilistic. Therefore, accurate predictions of our future are impossible (remember the "quantum superposition" we discussed earlier).

Secondly, even if we set aside the fact that the quantum particles behave probabilistically, it's not possible for us to make accurate measurements of their behaviors (remember the "uncertainty principle"). Therefore, we fail to even satisfy preconditions for making predictions about our future. Not only we are impossible to predict our future, but we are also impossible to, in principle, even get a grasp of this instantaneous moment.

Proving Existence of "Free Will"

Although these properties almost ensure our freedom (there is no way to prove that we are unfree), but I would like to prove the existence of "free will", just to make it doubly sure.

Actually, our free exists in the quantum world.

Every day we make a choice like either A or B, but we make these decisions quantumly.

I will explain how this mechanism works, using an analogy of choosing "soup" or "salad" in a restaurant.

The sequence how we handle our order in a restaurant

1) Consider your options of soup and salad (Make the quantum superposition in your head, with your choice being 50% soup AND 50% salad).
2) Choose "soup" using your will power (At this point in time, your choice does not affect the physical world at all; that is, the quantum state remains as 50% soup AND 50% salad).
3) Say "soup please" to your server, using your voice (the quantum state settles to "100% soup", which is chosen at Step 2)).

It is very important for you to make the quantum superposition at Step 1).
By means of this superposition, we can choose soup or salad on our free will, beyond any causality, because this dual quantum nature ensures us that we can choose either soup or salad, whichever we want, at the moment we are faced with the decision (remember the quantum superposition).

Still furthermore, no one can predict what we choose, also due to the quantum nature (remember the uncertainty principle).

Also note that nothing happens in the physical world as a result of the Step 2), where you exerted your free will. This means that our will is completely free from any past events, and its power will be exerted only on our future.

It may appear that your choice will would introduce some kind of statistical inconsistency, because it forcibly changes the probabilities to 100% for soup and 0% for salad, which were originally 50% for salad and 50% for soup. However, such an inconsistency does not occur, because your will power has a very special nature that its effect remains local and statistically random.


I've proven the existence of free will.

Well, do you say I proved nothing?

Yes, you are correct. I've proven nothing.

However, I believe that this discussion should be enough to convey what I wanted to say.

My true intention of this article is to suggest the possibility that free will do exist, and to assert that we can't arrive at any conclusion by doing examinations based on natural language, in the way we do with philosophy, for example.

There are times we face difficulties and ask ourselves questions such as "What is happiness?" or "Is there any meaning in my life?"

That's when we have to stop thinking.

These questions may not be what we should be asking ourselves.

When you are given with two options of your life being "meaningful" and "meaningless", which one does it make you feel better?

Once it becomes clear to us, we don't need to think any more.

No one can say which one of these options is "correct", because we live in a world where there are no such a thing as an "absolutely correct" answer.

Of course, neither philosophy nor physics gives you such an answer.

Then, there is only one thing we should do: just go ahead and live our future, believing that our life IS meaningful.

(Translator's Note)

While I was translating this text, I realized, as a linguistic practitioner, that the English words "quantum" and "particle" have different connotations from the Japanese counterparts ("量子 (child-sized amount)" and "粒子 (child-sized grains)").

Etymologically speaking, the English word "quantum" came from a Latin word quantum (portion, share), and the "particle" has the same root as those of words such as "part", "particular", and "portion".

These English words, at least simple words such as "portion" and "particular", are used not only in different academic fields, but also as a part of everyday vocabulary. However, their Japanese translations lack all of these connotations, and are often hard to grasp.

I've been having a feeling that these features of the Japanese language can lead to some kind of "academic sectionalism", and we Japanese people could miss the chances to enjoy the merits of interdisciplinary explorations.

Because this article is not a scholarly paper, and is intended to invite readers to make discussions with the author, I, who is the translator, personally love to hear the opinions of not only those in the fields of science, but also those in the arts.

We are merely "dwarfs standing on the shoulders of giants", and we don't need to impose any limitations on which "giants" we can depend on, to make this world a better place.

It will be wonderful if you, who understand English, can make contributions to deepen our insight on this subject matter. (A.U.)

If you agree with it, send it to a friend or share it on SNS!

Martin Luther King, Jr.
"The ultimate tragedy is not the oppression and cruelty by the bad people but the silence over that by the good people."

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1. Vincent C. Mitsch
[2021/05/13 08:24:16 JST(UTC+09:00)]

I always believed that learning Japanese would be the solution to many of the language difficulties I have in communicating with my family and peers. I find it both funny and sad that English gave me a better chance at understanding quantum reality. I believe I am the mirror image you have been looking for :)

2. Vincent C. Mitsch
[2021/05/13 08:39:23 JST(UTC+09:00)]

Free will exists. It has been proven (twice, now :L)

3. Fully Hatter
[2021/05/13 21:38:17 JST(UTC+09:00)]

> Vincent C. Mitsch
Thank you for your comment and thank you for your love of Japan.

I believe Japan has a wonderful culture that is comparable to Western culture, but the world is not very aware of it.
Only anime and games are famous...

4. Dimas Marda
[2021/05/18 10:48:29 JST(UTC+09:00)]

It's interesting and also its good conclution.
Free will certainly does exist, but will always has a connection with a universe where space and time co-exist. we sometimes have two or more choices, and oftenly even forced not to choose at all, which is why not choosing is also an option (materially).
Yet we can understand free will by an independent mind, detached from social expectations and free from life goals that do not belong to us. We always have free choice to always be happy and have gratitude even though we are old sitting on weathered rocking chairs.

5. Fully Hatter
[2021/05/19 16:26:30 JST(UTC+09:00)]

> Dimas Marda
Thank you for your comment!
It's an interesting point of view.

6. Steve
[2021/05/26 06:38:20 JST(UTC+09:00)]

Interesting, thank you. My starting position is that free will may be prejudiced and limited by our own socially-constructed psychic prison.

7. Fully Hatter
[2021/05/26 20:39:40 JST(UTC+09:00)]

> Steve
As you pointed out, we are certainly constrained by social stereotypes and beliefs.
But on the other hand, such constraints allow us to "judge".

The extremely useful tool "prejudice" allows us to make accurate decisions based on the vast amount of information we see every day.
If there is no prejudice, all possibilities will have to be reconsidered from scratch, and even the smallest decisions will take a tremendous amount of time.

Comment here, and Fully Hatter will reply with affection.

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