Pinned piece allowing mate

There's a rule I don't quite understand in chess. Say the Queen gives checkmate and it's defended by a knight, which is itself pinned against it's own king, the result is still checkmate. However, if the Queen attacks the King, but not giving checkmate, the King can just take the Queen because the knight is pinned. Or am I wrong? Can the King still not take the Queen in this situation? Don't know why I'm so confused about this. Been playing a lot of Tactics Trainer, so my brain is a bit scrambled!

The king still can't take the queen, because it would be in check.

Pinned pieces still give check. The explanation gets pretty deep in terms of laser-optics and marine biology.

Yeah, it's actually a double standard in the logic.  You say the pinned piece can't move because it would be check, but you allow the capturing king to move into check first.  As Ivandh alludes to, it's a lot like the specular reflection of plankton.

The answer is very basic: a K cannot put itself in check. Just keep that in mind.

All the rest that you are concerned about is what is confusing you. Forgedaboutit.

The pinned piece doesn't have to move, because the game isn't won by actually taking the king, it's won by the king being in check and not being able to get out of it.  You can't take the queen and say "I might be in check, but the knight can't actually move to take me."

Sorry, I don't think I explained my initial situation very well. It *slightly* annoys me that a pinned piece is still active, but yes, of course the king can't take the queen even though the knight couldn't theoretically recapture. 

There used to be a lot of debate concerning whether the game of chess would be slightly different if the King had to be physically captured rather than just put in checkmate. Perhaps if this was the rule, a pinned piece couldn't capture and therefore the King could go ahead and take the Queen. 

And can we stick to chess and not plankton?

thats a good point that scenario shouldnt be checkmate in real logical terms. i assume this is the type of position under discussion?

But surely the underlying princlpe of check is that ur king is going to get captured hence u have to move it, therefore if it cant be captured it shouldnt be check. We are always taught as kids that the aim of chess is capture the opponent king, which actually doesnt seem correct at all.

Not this again...!!!!

vacumm, you are basically saying that black should be able to play KxQ because white cannot move his pinned knight.

Illogical. You will allow black to move into check, but you won't allow white to move his knight, because.....wait for it....he will be putting himself in check !!!

Just remember that while a piece is pinned, it can still:

1.protect another piece that is giving check

2. give check itself.

but again the point of check is the king can be captured thats why its a forcing move, so it should be able to capture queen as that shouldnt be considered a "real" check

No, it's that the king is threatened.  It can't be captured.

There's no paradox here.  Check is defined as the king being under attack.

It's true that "you are not allowed to move so as to place your own king into check."   

Take the position in vacuum's post #8 for example.  KxQ violates the rule, so it's an illegal move, no need to think any further.

If you eliminate that rule, so that KxQ is allowed, then the response NxK is also allowed.  White puts himself in check, but that's OK under the new rules!  The black king is captured, so white wins.  Black never gets to move again and can't play BxK.

The "not putting yourself in check" rule is really just a courtesy.  I can't think of any situation where it would change the outcome.

(The rules about castling through or out of check are a different matter...)

Think about it this way. The game truely ends when the king is captured. But as the game developed we let the game end one move before that happens when the king can't escape. So in vacumms example, the sequence would be the king takes the white queen, then the white knight takes the black king (game ends before the black knight can move).

In this scenario we could logically think that the playe who captures the contrary king first is the winner. So when either king is captured, the game is over.

So even if i had a pinned piece, let's use your example, a pinned kinght is protecting the Queen giving check. If the King capture the Queen, then the knight captures the king, and the game is over, no time for another move, cause one of the kings have already been taken.

If it's stalemate, it's a draw. If the one player could move into check, he would lose, because his king gets taken next move.

The K cannot take the Q. Read what I posted above. The knight doesn't mysteriously lose its power to protect the Q just because it is pinned.

Your board posiion is chekmate, plain and simple. You may wish to invent new rules, but the rest of us prefer the current ones.

It would end withthe first king capture. KxQ NxK. The bishop cannot capture the king because his own king is already lost. One move short

ive seen a few peolpe have made this point, and it makes sense. since the black king will been captured first the game automatically ends and black doesnt have the time to recapture with his knight.