is the beautiful a matter of psychology? — tim wood

What is the other possibility?
(I am afraid that we will continue only later since I have to go now.)

Any intended simplicity is also merely another kind of sophistication.

This is why sophistication and symmetry very often contribute to beauty.
A chaotic art is not a disproof to this theory since its chaotic effect is intentional.

I will try to answer my question and you are welcome to comment.
I have found a common factor to the phenomenon of beauty: The extent by which the object seems to be designed thoughtfully. The more an object gives this impression the more it will be beautiful.
This is of course, not scientific, but many examples confirm this theory.
Again, the more there is an impression that there is a "thought behind" the object, the more the object will be beautiful.

Let's look through the entire life of a single individual, why is it that some things are beautiful to his eyes and some aren't?

There could be a cultural factor or some other reasons causing individuals to react differently to the same ballerina.

If that is what you meant to ask. These sub-experiences are reactions, I would say.

An important group is not required, unless one wants it to be importantly beautiful.

Let's talk about one individual experiencing beauty, what is this experience's origin?

Anyways, now that we have defined "beauty" (at least partially), can you help me find its general origin?

Now, I didn't get what you mean.

I agree that we feel that there is a difference between "appreciated" and "beautiful" but we can explain that this is due to the usually similar taste of people regarding beauty.

Why "appreciated" is not good enough for you?

Beautiful is just like tasty, no one is wrong!

I admit that "according" is confusing and should be omitted. I'm sorry for that.

Beautiful is just like tasty i don't want to be more confusing.

...

If there is a disagreement about whether something is tasty it is really not a disagreement and no one is wrong.

This is like the adjective "tasty."

I mean that beautiful will be always according to a particular beholder.

I should be honest I think that beautiful has many senses. When one says that something that is importantly accepted as beautiful is not beautiful, this refers to another meaning of beautiful.

They agree on a broader sens of beautiful: Appreciated by an important group of people.

I mean that, even if one decided that something isn't beautiful, it yet might be beautiful since someone else decided that it is beautiful.

I agree with that. The beholder decides whether something is beautiful. Although it might be yet beautiful since another beholder appreciates it.

The quality is that it is appreciated just as the example above of "wanted."

Consider the concept "wanted". What is the definition of "wanted"?
The quality of things that one wants. It is the same by beauty.

It's clearer to put it this way: This is a quality that is defined through the appreciation of the beholder.

It is a quality of sights and sounds that depends upon the beholder.

Beauty is the quality that hold sights or sounds that give rise to a pleasant feeling. More precisely, it is the quality of sights or sounds that give rise to a feeling of appreciation. This addition excludes for example, a pleasant feeling that is due to a sexual stimulation.

It seems that my initial formulation is far from being clear. I should try to ask this question in a much simpler way:
What is more important, the knowledge of the truth or well-being?
One of the implications is the answer to the following question: Should one rather believe in what brings one well-being or in what brings one closer to the truth?

The suffix -able denotes an ability and the prefix ir- denotes a negation. This means that irrefutable means "that cannot be refuted." I have used this term correctly, in a limited sense, but correctly. It cannot be refuted using the data available. It can be refuted however, theoretically.
This is what I meant by irrefutable.

Refuted means that it has been refuted in the past. This is clearly not what I meant.

I do! It is only irrefutable using the data currently available.
Just as in the examples I already gave. I will give one more:
There is life on planets other than earth. (This can be disproved only theoretically).

It is irrefutable in a sense but not completely. (I am afraid that this is very simple).

Obviously logic and mathematics have statements that are more than reasonable. Furthermore, their negation is even inconceivable: x+y=y+x, if the object is round, it is not square and so on.
My interest was in the other types of statement: Rich people are more stressed in their lives. Reading more than 6 hours straight is damaging one's vision and so on (these statements do not belong to the "more than reasonable" area and their negation is not inconceivable).

I also didn't mean to beliefs that cannot be doubted. I meant to beliefs that might be false. Irrefutable only means that it cannot be disproved using the data available.
Another example is the belief that there is a free will.

By irrefutable I didn't mean that one cannot disprove it even theoretically. Of course, a person can theoretically come back to life and tell us that he actually didn't stop to be conscious even after dying, but this is only theoretical.

By irrefutable I mean to negate claims like "it will rain tomorrow" since regarding these type of claims one has enough data to reasonably decide whether they are true or false.
Irrefutable in this sense, includes claims like "one stops to exist after one is dead."