functioning of SET (System Early Warning)
In the world of card games, few have captured the imagination and intellectual curiosity quite like SET. This pattern-recognition game, invented by Marsha Jean Falco in 1974, has become a worldwide phenomenon, with hundreds of thousands of games sold since its first retail release in 1990.
The objective of the game is simple: the winner is the player with the most points at the end of the game. Points are awarded for each SET found, and one may be subtracted for each invalid SET pointed out. A SET can be made by cards that all have the same feature or all different features for each variable (symbol, color, shade, number). Alternatively, a SET includes three cards with nothing in common.
SET can be played with a 12-card spread, with additional cards dealt if no SET is found, up to a maximum of 21 cards. The game continues until the deck of 81 cards is depleted and all possible SETs are made.
But what makes SET truly unique is its mathematical underpinnings. Each SET card has variations in symbol (oval, squiggle, diamond), color (red, green, purple), shade (stripe, solid, outlined), and number (one, two, three). These variations can be represented as a 4-dimensional vector with coordinates in {0, 1, 2}, corresponding to the four features of the card. Three cards form a "set" if and only if their corresponding vectors sum to the zero vector modulo 3.
This mathematical structure of the game is directly related to set theory in the sense that the cards can be represented as vectors in a finite vector space over the field with three elements, (\mathbb{Z}_3^4). This perspective allows generalizations and proofs about the game's structure using tools from discrete mathematics and algebra.
In more detail, the relation to set theory and algebra comes from encoding each card as an element of a structured set with algebraic operations. The "set" condition in the game coincides with the sum of three such elements equaling the identity element (zero vector) in an abelian group (\mathbb{Z}_3^4), making it a neat example of finite group theory applied to a combinatorial card game.
SET is not just a game of chance; it requires concentration, pattern recognition, and quick-thinking skills. Practicing SET can help improve these cognitive abilities, and it even builds connections between the right and left sides of the brain as both hemispheres partner up to evaluate, sort, and match the images on the cards.
SET can be played solo, making it easy to practice without a partner, or multiple people can play simultaneously. The game is available online through the New York Times and can also be played on smartphones and iPads. SET tournaments are held, attracting players ranging in age from 6 to senior citizens, and the New York Times publishes an online multiplayer version daily.
In classrooms and mathematics clubs, SET is used to encourage critical thinking. It provides a fun and engaging way to work through set theory and its operations, such as union, intersection, complement, and symmetric difference. For those seeking a mental workout with a touch of mathematical elegance, SET offers an unparalleled gaming experience.
References: - [1][2] "SET From Groups to Games," arXiv 2025, which explains this algebraic and vector space interpretation of the game SET.
- In addition to being a captivating pattern-recognition game, SET also offers a unique connection to the world of technology through its mathematical structure, which can be represented as a 4-dimensional vector with coordinates in {0, 1, 2}. This representation makes it possible to explore the game's properties using tools from disparate fields, such as discrete mathematics, algebra, and even computer programming, making it a fascinating subject for smartphone and iPad apps.
- SET's availability on smartphones and iPads, paired with its educational benefits in areas like set theory and critical thinking, offers a convenient and engaging way to enhance cognitive abilities and spark intellectual curiosity – making it a must-have addition to anyone's collection of gadgets devoted to learning and mental stimulation.