This video was made possible by Audible.
Try out Audible plus for free for thirty days by going to audible.com/HAI.
So, you want to totally ruin a fun little game from your childhood?
You’ve come to the right place.
Here’s how to never lose tic tac toe.
Step one: go first.
It’s usually best to say something like, “do you want me to go first, I don’t really
care,” and then make a move before they can respond.
And when you do go first, go in one of the corners.
Now, if your opponent goes in the middle, you might end in a draw.
But, if they go anywhere else, you can guarantee a win.
There are basically four non-middle places your opponent can play—technically eight,
but really four because the positions are duplicates if you rotate the board.
They can go next to you, in a corner near you, in the middle away from you, or in the
opposite corner.
If they go next to you, go in your nearby corner, but not with them in between you.
They’ll block you, then you go in this corner, and now you’ve won—because either they’ll
block you here, and you go here, or they’ll block you here, and you go here.
Now, if after your first move they hit you with the corner near you, just take the opposite
corner.
Then same thing: they block you, you go in the other corner, and boom, pop the sparkling
apple juice, you’ve won again.
If they start in the middle away from you, go in the corner touching them.
Then same thing, they block, you corner, you win.
And if they go in the far corner, just go in any other corner, and again, block, corner,
win.
Now, if they were smart, and they did go in the middle at first, don’t panic.
Play it cool, and go catty-corner to your first move.
If they then go in a corner, you go in the opposite corner and you’ve won—they’ll
block here or here, and you go in the other one.
If they go in a middle, though, you have to block them and sadly, you’re probably headed
towards a tie.
So, how do I know all this?
Well, because I read the tic-tac-toe Wikipedia page.
Well, actually I didn’t read the Wikipedia page, I paid a writer to read it for me, which
I was able to do because years earlier, I read the Wikipedia page on capitalism.
But how does Wikipedia know this?
Well, it’s because tic-tac-toe is what’s called a solved game.
Like ice cream flavors at a store that has very few ice cream flavors, solved games come
in three types.
The first type of solve is called “ultra-weak,” which incidentally is also the type of jokes
we use in these videos.
Basically, it means that the value of the start position is known—that value can be
one of a few things: either the first player can always win, the second player can always
win, or one or both players can always force a tie.
The thing about an ultra-weak solve, though, is that while you know the starting position’s
theoretical value, you don’t actually know what the winning strategy is.
For example, there’s a mathematical proof by Nobel Prize Winner and subject of the 2000s’
worst Best Picture Winner, John Nash, showing that a game of hex on any NxN board can always
be won by the first player.
While we know the winning strategies of small boards—from 1x1 up to 9x9—once we get
to bigger boards, we know the math says there definitely exists a way for the first player
to guarantee a win, but we don’t actually know what that way is.
The second type of solve is a weak solve.
That means that the value of the start position is known, and an algorithm knows how to get
to that outcome, but only starting from the beginning.
If you give a weak-solve algorithm a board already in play, with mistakes made, it’ll
go all blue screen of death and won't know what to do.
The third type is a strong solve—that means that you, or an algorithm, can figure out
the best possible move from every possible game position.
Mathematicians who apparently have nothing better to do have developed strong solves
for a ton of games, from tic-tac-toe, to Connect Four, to Chopsticks, often using something
called a minimax algorithm.
To understand, let’s rip-off Black Mirror and become an algorithm, by doing a minimax-style
analysis of a game played between our two beloved mascots that we’ve always had: giraffe
as interesting, and calf as interesting.
The only way to have a simple example is to invent a really boring game that would suck,
so, in this game, there are only two move options, left or right, and there are only
three turns: giraffe, then calf, then giraffe.
Here’s what’s called a game tree, which shows all the possible outcomes: giraffe wins
are in yellow, calf wins in purple.
So let’s work backwards.
We see here that in this outcome, it’s giraffe’s turn, and if they move left they win, if they
move right they lose.
They’ll always move left to win, so this position is a guaranteed giraffe win.
And in this position, they win either way.
That means on this half of the tree, no matter what calf does in its move, giraffe will win.
But on the other side, in this position, calf always wins, no matter giraffe’s second
turn.
In this one, giraffe can win—but, on calf’s turn, they can always just go left, meaning
this side guarantees a calf win.
But if we go to the top, we see that all giraffe has to do to guarantee a win is go left at
the beginning, meaning that this game has been strongly solved, and that the first player
will always win.
Theoretically, that same minimax algorithm analysis could solve any two-person game with
finite board positions; but before you start building a Magnus Carlbot, you should know
that games like chess or Go—both of which have more possible outcomes than there are
atoms in the observable universe, which is probably at least a thousand—are too complicated
for a minimax to be practically feasible.
For the time being, you’ll just have to settle for ruining tic-tac-toe for your friends
and family.
Remember: it’s technically not cheating, it’s just being a tool.
You know what else feels like cheating but isn’t: listening to audiobooks.
You get all the incredible storytelling of reading a book, plus the superior, smug feeling
of reading a book, without actually having to make your face holes read a single word
squiggle.
And the best place to listen to audiobooks is on Audible, the leading provider of spoken-word
entertainment.
Their newest plan, Audible Plus, gives you full, unlimited access to their Plus catalogue,
letting you listen to thousands of audiobooks, plus original audio dramas and podcasts.
It’s the perfect option for audiobook and podcast power-listeners like me.
I’ve been using Audible Plus since it came out, and the absolute favorite thing I’ve
listened to with it was Forward—a collection of short stories by some of the top science-fiction
writers out there, including Andy Weir of the Martian.
The best thing about Audible Plus is that it’s unlimited—you can try as many titles
as you want, and it still costs the same, so you’re guaranteed to find something you
like—and you can listen to Forward or anything else in their catalogue for free for 30 days
by going to audible.com/HAI.