The Unbeatable Game from the 60s: Dr NIM

Buy a modern version of Dr NIM!

The game of (single pile) Nim can be won by anyone who understands a simple trick. A trick so easy, a 1960s mechanical plastic computer can play with perfect strategy, defeating all humans.

Learn the method and proceed to beat your friends, family and colleagues.

Read more about single-pile Nim on the Maths Busking site:

My Domino Computer. The Domputer.

Dr NIM at the Computer History Museum:

And someone has put the whole instruction booklet online:

MATT PARKER: Stand-up Mathematician

Music by Howard Carter
Design by Simon Wright

[ProteinFromTheSea]

Idea: have 13 coins. Line twelve of them up, and flip the last coin to determine who will go first. If the flip says that you go first, add the last coin to the line, and act like that was what was going to happen all along. If the flip says that they go first, pocket the coin, and act like that was going to happen all along.

How to win: Use maths
How to win if the opponent has caught on to our strategy: Cheat

[angry_zergling]

That's pretty friggin' cool. Always amazed with the clever ways engineers could 'program' arbitrary rules or mathematical stuff to play out via purely mechanical means.

[devoid-of-life]

Dr. Nim hates him for this one simple trick

[mikosoft]

From the screenshot I thought Dr. Nim would have some mechanics hidden inside. It's simplicity makes it even more amazing. It's pretty much a mechanical flowchart!

[barneymcwhat]

played this with my young nephew. only instead of coins, marbles, or pegs, there were sweets. and instead of losing, if there were no sweets left to take, and it was your go, you'd have to take and bite into a wedge of lemon.

because what else are nephews for

[Rurike]

I remember seeing a version of this game on an old show called cyberchase, they even explained the same group of four trick and a version where you dont want to be left with the last marble. Kinda neat.

[seanhub]

Thank you for this explanation. I have a new proffession as a NIM gambler and have won alot of money using this strategy to outwit people on the playground, those year 7s will never see whats coming.

[JeffFrmJoisey]

I had Dr. Nim as a kid!! The manual was the most detailed, text filled set of toy instructions I ever got (not including model instructions). If I'm remembering correctly, there was a section at the end of the manual which explained computer programming or the logic needed for one. I remember using that info and programming my own Dr. Nim game in HP Basic on a "time share" HP1000 computer. Oh, and, it was saved on lunched yellow paper tape that you had to reload to play.

[breakingaustin]

*Doctors hate him! Australian man beats game with this one simple trick!*

[Ben_the_Rosafan]

Now I'd really like to see Matt do a video on the Mario Party 2 minigame "Honeycomb Havoc". It's basically an inversion of Nim: 4 players, you can take 1 or 2 items on your turn, and the object is to NOT take the last item, whoever does is eliminated.

[tejasviization]

The levels of video editing is unreal on this on. (Multiple Camera Angles and Text Overlay WOOT!!!)

[x]

You could simply sum up the strategy in one single sentence: Make sure there's a multiple of 4 tokens on the table when it's your opponent's turn.

The game was actually pretty popular with aging con men that didn't have the speed in their hands anymore to swindle money out of people with the three shell game.

But the mechanical implementation is really awesome.

[finn_underwood]

So... to win when you go first, you discretely add a coin?
Correct me if I'm wrong, but that sounds an awful lot like cheating...

[nickhersheys]

Here is a trick to slip in an extra coin in case you are the first one to play. Or lets say there is a dispute to who plays first.
Throw 12 coins on the table .(Not in a straight line. You can place the last coin with dollar bills aside)
Now take an extra coin out of your pocket and ask the other player for heads or tails and the winner plays first.
If the other player wins the toss, GREAT ! Put the toss-coin back in your pocket and let the game BEGIN !.
If YOU win the toss, no problem, casually put the toss-coin in the play to make it 13 coins :) and let the game BEGIN !.

[johnbeauvais]

Wow, that's pretty impressive the level of design of a plastic kids toy in the 1960's, also way to teach kids the system is rigged against them.

[williammitchell]

thank you for telling me how to hustle drunks at a bar

[jordangraham]

At 5:23 - "Um sir, you have 13 coins."
5:25 - *Removes a coin* You were saying?

[drewboozer]

"You can tell it's 1960's America because there's a wholesome family having fun, with GUNS in the background."
I'd like to say you're wrong but it's very true

[liams]

I remember playing a game like this with my second grade class called 21, where you could say one, two, or three numbers in a row, and whoever said 21 lost. So, for example, player one goes 1, 2 then player two goes 3, player four goes 4, 5, 6. Then if someone had to say 21, they were out and we started again. The last person left won. I remember being very proud of myself for finding out the trick described in the video