This idea is equally valid for chess. If you know what’s the position you are striving for, life gets a lot more easy.
See the diagram. Please do not move the pieces on your chess board and work it first out in your mind.
In this position white played 1. Nd6. The threat is quite obvious. If black doesn’t do anything meaningful he will be mated. 1… [any non meaningful move] 2. Qh8+ Ke7 3. Qg7#
Another line is: 1… Rxh7+ 2. Nxb5 Rxd1 3. Rxd1 Rxh2 4. Kxe2 Ba6 with (some) advantage for white.
Okay, it is more or less clear: if black wants to save his skin, he has to do something very forceful, otherwise he has a problem. Maybe you say to me at this moment:
‘Michel are you kidding me, why all this talk? Isn’t it clear to you that black has a double check?’
Of course. It is the first thing every chess player would see. We can’t miss it. Our eyes are drawn to it.
But that’s exactly the point I am trying to make. What’s the follow up for this move? Moreover: first glances aren’t always right. Sometimes they are plain stupid. Just think about the suggestions kibitzers make while commenting on grandmaster games during a tournament. They make terrible mistakes. Me included. Simply because we are not completely familiar with the position. In our eagerness to act, we tend to overlook all sorts of obvious stuff.
I remember one of my own games. I was thinking for almost twenty minutes and worked out a lot of wonderful moves. I failed to see that my opponent was threatening a very simple mate. In this case I was lucky. Just before I wanted to make my ‘brilliant’ move, I realized what was going on. It took me a couple of minutes to recover from the shock. I was too busy with my own plans.
I see the same thing happening with vote chess. People suggest moves that are completely losing, sometimes within one move. And I do not exclude myself from this notorious club of patzers. We can’t rely solely on our intuition. Chess players need to calculate and be precise.
But in this case you are completely right. Black has to act with force and the only really forceful move is a double check with the knight. 1… Nxg3+ But what to do after 2. Kg1? If you haven’t seen it on beforehand, it will be clear now. There is a mating pattern. To be honest: it took me a couple of minutes to figure this out from the original position after 1. Nd6. But then I suddenly saw the light. Did you see it too?
Of course you did! 2… Qf1!! 3. Rxf1 3. Ne2# Isn’t this a beautiful combination? These combinations are quite easy to find if you have a couple of mating concepts in your mind. If only you know were you are heading to.
PS. 1… Bg2+ would also win: 2. Kxg2 Qc6+. But it is far less convincing.
EPS. White didn’t have a perpetual (check) in the original position (before he played Nf7-d6).