Retrograde Analysis: How to Solve Problems by Working Backwards.


In my previous article, I wrote about the “Inversion” technique for solving difficult problems by working backwards.

Another powerful way to solve difficult problems is by using the chess “Retrograde Analysis” method. In simple terms, retrograde analysis is a technique used in chess to solve difficult chess problems by working backwards from known outcomes.

Here’s how it works…

Retrograde Analysis to Solve Complex Problems 

“Complaining about a problem without proposing a solution is called whining.”

–Teddy Roosevelt

The game of chess is a good metaphor for life. Every day you have a bunch of decisions to make and difficult problems to solve.

For example, during a game of chess, within the first four moves, you would have over 300 billion choices of moves to play.

According to Chess Grandmaster, Maurice Ashley, the retrograde analysis is his preferred strategy to “see into the future” and make the right choices.

“What you do with retrograde analysis…is that in order to look ahead, it pays to look backward.”

–Maurice Ashley

The secret is that working backwards could even prevent problems from arising in the first place.

Here’s a breakdown of the retrograde analysis from Maurice Ashley’s Ted Talk.

How to Use Retrograde Analysis to Solve Problems.

Here’s a quick summary of the examples given in Maurice Ashley, Retrograde Analysis, TED talk,

Sentence reading example

After reading this sentence, you will realise that the the brain doesn’t recognise a second ‘the.’

Read that again a second time. You probably missed the second ‘the the’ first time. But here’s the trick: if you read the sentence backwards, you’d catch it.

Doubling Bacteria

Consider the doubling bacteria problem. Bacteria double every 24 hours. It takes 30 days to fill a lake. On what day was the lake half-full?

Hint: solve the problem backwards to get the solution.

Card game

Imagine there are six cards in this game numbered 1 through 6. Whoever has the highest card wins. You pick a card and it says the number 2. I pick a card and offer a trade. Most people look at their card and say, 2 sucks. Looking only at this problem statistically, you’re best to trade your card. However, assuming no trickery on my part, that may not the right move.

To solve the problem, invert. If I had a 6 would I trade? No. What about the number 5? … Odds are I have a pretty crappy number if I want to trade.

Applying the Retrograde Analysis in Your Life

Here are few suggestions on how to apply this strategy. 

Plan your goals backwards

Instead of planning your goal by working forwards, why not plan the goals by working backward. 

For example, if you want to lose 20 pounds in 5 months, then work backwards from your desired outcome. 20 pounds lost in 5 months is 4 pounds lost per month. 4 pounds lost per month is 1 pound lost per week.

So from there, what do you need to eat per week to lose 1 pound per week? How often would you work out per week?

By working backwards, you can create your own customised solutions to make it easier to achieve your goals.

Simplify your choices

On a daily basis, we are bombarded with way too many choices to make, but the most productive people simplify their decision-making processes to prevent the depletion of their willpower.

For example, Mark Zuckerberg wears the same type of outfit—blue jeans, gray T-shirt and a hoodie—on a daily basis. He credits his simplicity for helping him stay productive all year round. You can apply the same strategy by working backwards to simplify your daily choices.

The retrograde analysis will help you to reduce the number of possible decisions you make on a daily basis.

Live Life Backwards

The Retrograde analysis is a powerful way to solve difficult problem by working backwards. Just like the game of chess, future life problems can be solved by looking backwards.

It’s a thinking skill that requires doing the opposite of what you’d normally do by planning forwards. But, it pays off because it helps you to solve difficult problems easier and quicker. 

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