This one hurts.

I think this particular quirk of the human brain has caused more pain for Chess players than the rest of our quirks put together.

Forgetting sucks.

These are the big blunders. The inexplicable, out-of-nowhere, how-the-heck-did-that-happen blunders. The ones we beat ourselves up about.

Many adult improvers feel they are lower rated than they should be. If we're honest, most of us feel that way. The ones for whom that is actually true are likely held back by Forgetting.

If you're one of the players who contacted me about your jump in rating after starting with my work, Forgetting is probably the main thing you reduced.

I could write a whole series just about Forgetting and how it affects us. I should do that one day.

The cause of Forgetting is simple.

You're calculating a kingside attack, but it's complicated. Your working memory runs out of space. Your labrador, ever the faithful servant, tries to help.

It sees you're focused on the kingside and it desperately wants to make space so you can keep thinking about the kingside.

To achieve that, it sacrifices the memory of that long-distance bishop on the queenside. Or that fork your opponent's knight has been threatening for five moves. They become invisible to you.

With that extra space, you finish your calculation. You play your move with excitement and purpose.

Once you've made the move, your working memory frees right up. Full board awareness comes flooding back.

Oh no...

Your opponent's bishop takes your queen. Their knight gets its fork. You resign.

After these sorts of mistakes, you throw your hands in the air and consider quitting the game for good.

The bishop was right there! How could you possibly miss it?!

It's not that you missed it. It's that your brain let go of it. And that's a critical distinction to make.

When we overload, the part of our brain that makes decisions about what to keep and what to sacrifice doesn't understand Chess. It's a labrador; loyal, well-intentioned, a bit dumb.

In Part Two, we explored how the process of "thinking" is actually a few different functions working together. When your working memory is under too much pressure, your labrador makes rapid decisions about which functions to keep and which to drop.

Freezing is the result of your labrador holding on to information by sacrificing thinking space.

Forgetting is the opposite. To make room for more thinking, your labrador dropped information.

The information it decides to drop isn't random. Your labrador's main goal is to help you keep doing whatever it is you are doing. It works out what's important or not based on what has your attention in that moment.

It doesn't understand that your opponent has a mate threat. Or that the g4 square is protected and you shouldn't put your queen there. If you don't have active attention on those details, then they're at risk of sacrifice.

Think about the times you've Forgotten something "obvious" in your games. The detail that slipped was not a detail you were focused on. It was on the darker edges, just outside your spotlight of attention. That's the danger zone.

It's the bishop on the other side of the board. The weirdly placed knight that doesn't look like it's doing anything. Those are the killers.

Forgetting isn't only about pieces. It applies to anything that our working memory is juggling, including threats, plans, and ideas contained in the position.

When I was starting out with Chess, I struggled with one form of Forgetting in particular. I call it "unsolving a problem".

My opponent creates a mate threat. I place a piece, maybe a knight, to block that threat. And play continues for another move or two.

In that time, my attention shifts to another part of the board. I see a decisive opportunity and move my knight to take advantage of it!

... then my opponent checkmates me.

Obviously.

Because I moved the knight that I had expressly put there to solve that problem.

I Forgot the threat existed. My labrador decided I didn't need that detail any more.

Similarly, we can Forget the decisions we've made about the position or our own moves. This is another mistake I was particularly prone to.

It's a complex position. I have a few candidate moves. I calculate the first one that jumps out at me. At the end of that line, I realize I'll lose a bishop. Clearly a bad move.

So I calculate the other two options. But they're complicated, unclear. I see my time ticking down, the pressure ramps up. Eventually, it gets too much and my labrador jumps in to save me.

I play the first move I considered, hit the clock. I realize my mistake.

I just played a move that I'd already decided was bad!

They play their move, I play my move, they take my bishop. Just as I'd calculated.

Brutal.

Pieces, threats, ideas, decisions, whatever. As far as our brain is concerned, it's all just information. All up for sacrifice if it doesn't have our direct attention.

The aftermath of Forgetting is familiar to every Chess player, but it's impossible to spot while it's happening.

There's no part of our brain that alerts us when we've Forgotten something. We think we have it all. We make decisions as if we have it all.

But we don't.

To resolve issues of Forgetting, we need to do the work ahead of time.

There are 3 approaches we can take. I recommend doing all 3.

First, we can build familiarity with the key positions, patterns, and ideas in our openings.

If you have a strong understanding of the sorts of ideas, goals, and structures that emerge from your opening, you'll have to use less working memory space to navigate it. You're far less likely to Forget something in the moment if you're already familiar with it.

"Key" is the key word. Learn the really important stuff, and ignore the less important stuff.

Don't go overboard here. Lots of adult improvers waste lots of time on openings.

Second, we can build habits to catch some of these mistakes before they happen.

I'm on the record as being skeptical of blunder checks. They're an unreliable safety net at best. In particular, they don't help much with mistakes caused by Forgetting.

Because, again, it's not that we've seen the bishop on that diagonal and decided to place our queen in its sights anyway. It's that the bishop has vanished from our mind entirely.

If your labrador has decided to Forget the bishop, it'll likely stay invisible during your blunder check anyway. We don't magically get more working memory space just because we've decided to check for blunders.

That's not to say blunder checks are useless, they do help catch some things. But they're not a be-all and end-all solution that we can rely on.

To my mind, the best habits need to occur upstream, at the start of the move. We need to help our brain notice and remember these details before we start picking what to play.

Choose either the Vacated Square habit (easier to do) or the Mantra habit (harder, but more comprehensive) and start practicing it on every move. It will take a while, but eventually you'll train your brain to start doing these things automatically.

Also, experiment with doing full position evaluations every 3-5 moves (I explained the KMAPS structure in Part Two). This can help you to refresh your memory of the bigger picture position, and reduce the chances of Forgetting-related tunnel vision.

The final thing we can do is train our brain to be more efficient with board information in the first place.

Help it to do more with less working memory space. Make your labrador less skittish.

This is where conceptualization training comes in. But I'll talk more about that in a couple of weeks.

Forgetting causes our most painful blunders. When they happen, and they will, remind yourself that it's not because you're stupid. Or lazy.

They happen because there's a little part of your human brain that's trying desperately to help you. It's doing its best, but it doesn't understand.

Be kind to it. And be kind to yourself.

You can reduce these mistakes with the right habits and the right training. But they'll likely never go away entirely.

Even at the top level, there are plenty of examples of Forgetting.

You don't need these mistakes to go away entirely. Any amount of progress in this area could have a big impact on your game.

Hang in there. Recognize these blunders for what they are. And do the work.

You'll get there.

Here's to the journey,
Aiden