Hello everyone! My name is Dan, I work at the Main Library, and I love games. In this series of posts, I’m going to be teaching you how to play some classic games that are easy to learn, fun to play, and quite possibly already in your home! Today’s game might be the simplest one yet in terms of equipment: you just need your own hand and a friend to play with. Let’s learn about Rock, Paper, Scissors! 

Rock, Paper, Scissors (also known as ro-sham-bo) is one of those games that feels like it’s always been around, but it originated in China and Japan and only made its way to the Western world in the 20th century. Since then, it’s spread widely, probably due to it being an easy way to make a decision between two people without much stakes in the outcome. 

The rules are simple: The two players stand facing each other and chant “Rock, Paper, Scissors” while swinging a hand closed in a fist down in rhythm with the words, either hitting it against their other palm or just by itself. Then, they simultaneously say “Shoot” and make one of the three hand signs: 

Rock (hand in a fist) 

Paper (hand flat) 

Scissors (two fingers out in a V) 

(Note: some people prefer to make the sign on “Scissors” and don’t say “Shoot”. It’s very important to work out which way you are going to play before you start to avoid arguments.) 

Each of the three signs beats one of the others and loses to the third. Rock beats scissors (crushing them), but loses to paper (is covered by it). Scissors beats paper, but loses to rock. And paper beats rock and loses to scissors. If both players throw the same sign, play again. You can play just once, or in a best-of-three/five/seven/etc. series. 

This is largely a game of chance, of course. If both players choose randomly, there is a 1 in 3 chance of winning, losing, or tying with any given throw. However, it is possible to find a strategy, because people generally don’t choose in a completely random way. If your eyes are particularly sharp, you might be able to figure out what your opponent is about to throw by watching them carefully. Another method is predicting how your opponent will react to your choices: for instance, you might throw rock several times in a row, which will encourage the other player to use paper. Then you abruptly switch to scissors and take advantage of that. If you play enough with a particular person, you might be able to pick up on patterns in their choices. 

Plenty of variations on Rock, Paper, Scissors exist. Probably the most famous (as a result of its appearance on The Big Bang Theory) is Rock, Paper, Scissors, Spock, Lizard. This adds two more hand signs to the game: Spock (The Vulcan salute from Star Trek, where two fingers form each side of a V) and Lizard (holding the hand in a mouth shape, as if you were using a sock puppet). Spock beats rock and scissors, but loses to paper and lizard, while lizard beats paper and Spock and loses to rock and scissors. This variant makes ties less likely and the game more strategically complex. 

Interestingly, rock/paper/scissors-like dynamics even occur in nature. The side-blotched lizard, common in the western United States and Mexico, has three types of males, characterized by their throat colors: orange, blue, and yellow. The orange-throated lizards are the biggest and strongest, and easily bully the smaller blue-throated lizards, dominating large territories and mating with many females. The blue-throated lizards control smaller areas and generally only mate with one female. The yellow-throated lizards, despite being the smallest of the three, use an interesting strategy: because their size and coloration is similar to the female lizards, they can sneak into the territory of orange-throated lizards and mate with the females there. This strategy is ineffective against the blue-throated lizards, however, as they are more focused on their smaller territory and single mate. 

Rock, Paper, Scissors is a simple game, but maybe one with more depth and interesting aspects than you expected. Want to know more? Check out these materials from our online and physical collections! 

The Legend of Rock Paper Scissors by Drew Daywalt (Hoopla ebook) A fun picture book that gives a “origin story” for the game. (Place a hold on one of our copies here

Mixed Strategies and the Art of Bluffing (Kanopy) A talk on how to build a winning strategy in Rock Paper Scissors and other games, part of a series on the mathematics of games and puzzles. 

Rock Breaks Scissors: A Practical Guide to Outguessing and Outwitting Almost Everybody by William Poundstone (KCKPL collection) Some tips how to win at Rock Paper Scissors (and a number of other situations as well). 

More information on the side-blotched lizards and their rock paper scissors strategies (From UC Santa Cruz) 

If there are any games you would like to see me cover in a future post, let me know in the comments or send me an email at dable@kckpl.org. Happy gaming!