>>>>>>>Chess logic question:
>>>>>>>
>>>>>>>Assume that you have a situation where the King is in check from more than one piece. Is it possible to have such a situation where you can move one piece, other than the King, and get out of check?
>>>>>>
>>>>>>I don't think so. I've tried various combinations and although I haven't tried hard enough, I don't see a way.
>>>>>
>>>>>What about en pessant? It should in theory be possible to move the pawn to another column, taking out the piece putting the King in check while at the same time blocking another piece checking the King.
>>>>>
>>>>>Other thn that, I cannot see how.
>>>>
>>>>The piece that you take out would already have blocked the other piece from checking the king. In other words, only one piece would really have put the king in check. I hope my explanation makes sense.
>>>
>>>If you had a black Knight between the White King and the black Queen, you could move the knight in such a way as to cause double check. What I cannot figure out is if it's possible to counter by moving only one piece.
>>
>>Yeah there are a zillion ways to cause a double check - but only way out of it is to move the king.
>
>I entirely agree that it is not possible to escape a double check except by moving the King. But I am struggling to come up with a formal proof :-}

It's actually pretty simple - you can't capture both checking pieces or block both lines of attack in a single move, so the only way out is by moving the king.