Why A king cannot go to a square "covered" by an opponent pinned piece ?

I have a question that has been bothering me for years about chess that I can't get out of my head. I would like to have your opinion. I find all the rules quite logical and harmonious with each other. Even the en passant rule, which is strange for beginners, has a kind of logic to it when you explain it from a historical perspective.

On the other hand, there is one thing that I really, really don't find logical and I'm surprised that no one talks about it. Why can't a king move to a square that is covered by an opponent's pinned piece?

Here is a position illustrating my though. In a perfectly logical World, I think I should be able to play KC4 here. The king cannot be taken in the next move, so technically, it shouldn't be in check ?

The french Federation states that a king is in check when he is "attacked". Then explained there are three option when in check : the king can move, something can block, or something can take the attaquing piece. In my exemple, if my king is on C4 and I do non of those things, my king cannot be captured, so is it in check ?

I spoke about it with a lot of people and didn't received a convincing response so far.

If you accept that the King should never be captured, it makes sense because of something like this:

https://lichess.org/analysis/8/4p3/3r4/2k5/8/3Q2B1/3K4/8_b_-_-_0_1?color=black

Kc4 black walks into the queens square then Bxd6 and then Qxc4. I don't know how to prevent this other than the rule.

Otherwise you'll need to fully compute before each king move if it could possibly lead to a capture. Some move might always Pin or unpin something eight moves down, that would be impractical.

Think about chess from the point of view of taking a king. If you play Kc4 in this position, White can capture the Black King before Black can capture the White King.

Moving a pinned piece is usually illegal because it would allow the King it is pinned to to be captured before the game ends. In this case, it doesn't.

oh, that makes sense. for some reason I was focused on the "absolute pin" freezing the piece. completely missed the fact that if my rule would be in effect, the pin then would not be absolute anymore and the queen could take, ending the game first.

I feel both dumb and more intelligent now

@corvusmellori said in #3:

Moving a pinned piece is usually illegal because it would allow the King it is pinned to to be captured before the game ends. In this case, it doesn't.

Good point too. If Kc4, Qxc4 and the game ends is the white king then still in danger?

Would we have to play on without the black King to find out? What if the capture revals an attack on my King but I'm in time to capture yours first?

Questions that are better left unanswered, thanks to this petty neat rule. Maybe a new variant though? ;)

@val1313 said in #1:

On the other hand, there is one thing that I really, really don't find logical and I'm surprised that no one talks about it.

There are anonymous groups where especially this subject is discussed. maybe you should join one.

This topic has come up before, and besides the good point made by @corvusmellori in #3 the move Kc4 is also against the FIDE rules.

https://lichess.org/forum/game-analysis/why-cant-i-take-whites-rook-here#4

@lonelypeanut said in #5:

What if the capture revals an attack on my King but I'm in time to capture yours first?
Here is a fun position to work out these kinds out questions.

1. Nd5#

Consider what could happen if Black were to play something like Kf3+ (possibly Kf3#? unclear!)

Here I think the logic would make white say : ok My king is in check, and next move he is gonna die. But still, blacks king dies first. and then, as soon as he dies, all Blacks pieces, like the animals in the begining of The lion King, would stop what they were doing and bend before the White king even though they were just one step away from touching him. #savedbythebell

Great checkmate