The position of checkmate is achieved, according to the rules, when a piece ATTACKS the enemy kings square, and the king cannot escape. Attack is an action. The rules say both "attack" and "attacking". I think any reasonable person would agree those are action words. Or verbs.
Again, nobody is questioning which piece moves. But the attack, the ACTION, of checkmate, in our examples is not carried out by the piece that moves, the active checkmating piece is the discovered piece. The "position" of checkmate is not mentioned in the rules. But the "position" of checkmate ONLY happens because of the active, attacking piece that checks the enemy kings square.
You mean your own personal interpretation. Common sense actually says the piece that checks causes checkmate. ...
This does seem to be an interminable argument.
Of course, in the absence of a definition of "the piece that causes checkmate" by a recognised body, anybody can, like Humpty Dumpty, have their own personal interpretation.
But it's definitely not common sense to say that the piece that checks causes checkmate.
Checkmate is a situation where the king of the player to move is in check and the player has no legal move. There's no sensible reason to restrict consideration only to the fact that the king is in check. On your basis one might just as well say that the checkmating piece in the following diagram is the Black pawn on d2, because that piece is causing Black to have no legal move.
Of course you could choose any piece other than the Black king, so the use of "the" would be questionable, but so is it in your interpretation. Which is the checkmating piece here?
I agree with @KieferSmith and @Arisktotle that the only interpretation that conforms with common sense is "the piece that last moved".
I understand. However, the rules speak of the enemy king under attack. The attack does not come from the piece that moved. The attack comes from the piece that checks.
The rules are silent on defining which piece delivers checkmate, they only speak to the attacking requirement, not HOW a piece came to be the attacking piece. A great example was provided by Keifer. The car that gets out of the way did not cause the collision did it? The car that collided with the other car caused it because it was the car that was going too fast.
It would be hard to find a reasonable (or common sense) interpretation that agrees the entity that gets out of the way is the party responsible.
Sometimes the checkmating piece is the piece that last moved, sometimes it isn't. It depends on if it's attacking the enemy kings square. I try not to insert my own interpretation into the rules, I'm not an arbitrator. I don't think it's a good idea to add things that aren't there, like "the last piece that moved". I just go by what the rules say. And the rules say checkmate is when the enemy kings square is attacked, and the king cannot escape. Only the attacking (checking) piece can do that. A piece that is not attacking the enemy kings square is not mentioned in the rules (there could be a dozen pieces that are not attacking the enemy kings square).
Although the rules imply the attacking piece is the checkmating piece (because it mentions that requirement) there is literally nothing in the rules that imply the last piece that moved is the checkmating piece. Literally nothing. If there is, could you tell me which rule that is?
THAT IS THE POSITION OF CHECKMATE NOT THE ACTION FOR CRYIN OUT LOUD