What is a game?
EST310/ISE340
Fall 2011
Tony Scarlatos
Games through the ages
• c. 5000 BC – Dice (Assyria)
• Originally fashioned from animal knuckle bones, used in
divination (fortune telling)
• Introduces random chance into gameplay
Games through the ages
• c. 3000 BC – Royal Game of Ur (Mesopotamia)
• A race game, probably the ancestor of
backgammon
Games through the ages
• c. 3000 BC – Senet (Egypt)
• The game may have originally evolved from a calendar
• The game had religious significance, it is mentioned in the
Book of the Dead
• Below left: Queen Nefertari plays Senet
Games through the ages
• c. 3000 BC – Mancala
• A “sowing” or “count & capture” game
• Mancala comes from the Arabic word “naqala”, meaning “to
move”
• May have evolved from a crude calculator (e.g. a type of abacus)
Games through the ages
• c. 1500 BC – Nine Men’s Morris
• A two-player strategy game, the name refers to the number of
player’s pieces, the objective is to capture opponent’s pieces
• Popular from the Roman empire through the Middle Ages
Games through the ages
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c. 100 AD – Tabula
The name means “table” in Latin
Direct ancestor of Backgammon
Below: citizens of Pompeii play
Tabula, captured in a fresco
Games through the ages
• c. 400 AD – Go (Japan)
• Comes from Chinese game of Wei-qi (c. 1500 BC)
• 2 player strategy game
Games through the ages
• c. 1100 AD – Chess (originally 650 AD from India)
• Below right: Knights Templar play chess
• Bottom: the famous Isle of Lewis
chess pieces
Games through the ages
• c. 1400 AD – Tarot and other card games
• c. 1600 AD – Cribbage
• c. 1800 AD - Bridge
Games through the ages
• 1860 – Milton Bradley publishes The Checkered Game of Life
• 1960 – The game is reintroduced, simply titled “LIFE”
Games through the ages
• c. 1900 – Chinese Checkers published in the west
• 1924 – The Landlord’s Game, predecessor to Monopoly,
patented by Elizabeth Magie
Why play?
• Voluntary and intrinsically motivated activity, for ‘pleasure’
• Evident among all species with complex nervous systems (i.e.
mammals & birds), especially when they are maturing
• “Rehearsal for real life” – preparation of skills that will be
needed later – with lower risk/consequences
• Social play, locomotor play, and object play are three
commonly identified types
• Neuroscientists generally hold that play helps to “wire” the
connections in the cerebellum as the individual matures
Play
Benefits of Play
• American Academy of Pediatrics:
“free and unstructured play is healthy and – in fact – essential for
helping children reach important social, emotional, and cognitive
developmental milestones as well as helping them manage stress and
become resilient.”
• UN Convention on the Rights of the Child:
“Parties recognize the right of the child to rest and leisure, to engage
in play and recreational activities appropriate to the age of the child
and to participate freely in cultural life and the arts.”
• Play as a foundation of learning has been espoused by
psychologists such as Jean Piaget and Lev Vygotsky, as well as
technologists such as Seymour Papert
Games, Puzzles, and Toys
• Toys: no rules, no goals
• Puzzles: few (mostly implicit) rules, but a goal
• Games: rules and goal
• Is playing with dolls a game?
• Is a crossword or jigsaw puzzle a game? Is
building a model airplane a game?
• Is soccer a game? Is skiing?
• Why is a global sports event called “the Olympic
Games”?
So what is a game?
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Play activity
Pretend reality
Achieve a goal according to the rules
The “Magic Circle”: the play space (tennis court, court of law,
temple) separate from real life
The Magic Circle
“All play moves and has its being within a play-ground marked
off beforehand either materially or ideally, deliberately or as a
matter of course. Just as there is no formal difference
between play and ritual, so the ‘consecrated spot’ cannot be
formally distinguished from the play-ground. The arena, the
card-table, the magic circle, the temple, the stage, the screen,
the tennis court, the court of justice, etc, are all in form and
function play-grounds, i.e. forbidden spots, isolated, hedged
round, hallowed, within which special rules obtain. All are
temporary worlds within the ordinary world, dedicated to the
performance of an act apart.”
- Johan Huizinga, Dutch Historian (1872 – 1945)
The Magic Circle
Goals and Rules
• Goal: Victory and/or Termination condition
• Rules:
– Semiotics: symbols and tokens
– Gameplay: challenges and actions
– Metarules: rules about rules
Game Theory vs. Gaming Theory
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Game theory is a study of how people interact and make decisions. Specifically it
attempts to provide a mathematical model for calculating a player’s success based
on the decisions of others.
Modern theory is credited to John Von Neumann (Theory of Games and Economic
Behavior, 1944). John Nash (subject of the movie “Beautiful Mind”) generalized
the results and provided the basis for the contemporary field (Nash equilibrium, c.
1950).
The applications of Game Theory are mainly in the social sciences – Economics,
Sociology, Political Science. Its application to Computer Science, specifically games,
is in Artificial Intelligence.
Gaming Theory, or Game Studies, is a subset of a field called Ludology (the study
of play) which includes all games, not just digital ones. Game Studies has a much
more cultural context. Its application in Computer Science is the study of the
design and development of computer games.
Game Theory may be confused with Game Studies, but they are very different.
More About Game Theory
Five Elements of a Game
• The players
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how many players are there?
does nature/chance play a role?
A complete description of what the players can do – the set
of all possible actions.
The information that players have available when choosing
their actions
A description of the payoff consequences for each player for
every possible combination of actions chosen by all players
playing the game.
A description of all players’ preferences over payoffs.
More About Game Theory
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A zero-sum game is one in which the players' interests are in direct conflict (e.g. in
football, one team wins and the other loses; payoffs sum to zero).
A game is non-zero-sum if players interests are not always in direct conflict, so that
there are opportunities for both to gain (e.g. Prisoner’s Dilemma).
Below, the Prisoner’s Dilemma in Strategic form. If neither Player confesses, each
gets 1 year. If both confess, each gets 5 years. If only one Player confesses, he goes
free and other gets 15 years.
The highest payoff (lowest sentence for the prisoners) requires implicit
cooperation between the players.
Player 1
Player 2
Don’t Confess
Confess
Don’t Confess
1,1
15,0
Confess
0,15
5,5
More About Game Theory
• Games where players choose actions simultaneously are
simultaneous move games.
– Example: Prisoners' Dilemma
– Must anticipate what your opponent will do right now,
recognizing that your opponent is doing the same.
• Games where players choose actions in a particular sequence
are sequential move games.
– Example: Chess
– Must look ahead in order to know what action to choose
now.
More About Game Theory
• One-shot: play of the game occurs once. Players are
not likely to know much about one another.
• Repeated: play of the game is repeated with the
same players.
– Reputational concerns matter; opportunities for
cooperative behavior may arise.
• If you plan to pursue an aggressive strategy, ask
yourself whether you are in a one-shot or in a
repeated game. If it is a repeated game, you may
wish to think again.
More About Game Theory
• Cooperative games are games where players can form binding
commitments to each other.
• In Symmetric games payoffs depend only on the strategies
employed, not who plays them. In Asymmetric games the
strategy sets are not the same for all players.
• Perfect information games include chess; Imperfect
information games include poker. Only sequential games can
be Perfect information games.
• Combinatorial games (like chess) have such a multiplicity of
actions that an optimal strategy is difficult to find.
More About Game Theory
• Payoffs are known and fixed.
• All players behave rationally.
• They understand and seek to maximize their own payoffs.
• They are flawless in calculating which actions will maximize their
payoffs.
• The rules of the game are common knowledge:
• Each player knows the set of players, strategies and payoffs from
all possible combinations of strategies: call this information “X.”
• Each player knows that all players know X, and that all players
know that all players know X.
• In equilibrium, each player is playing the strategy that is a "best
response" to the strategies of the other players.
Game Studies
1. Social science approach
Studying the effects of games on people
What do games do to people?
(e.g. learning, effects of violence in games)
How do people create and negotiate a game?
2. Humanities approach
Studying the meaning and context of games
What meanings are made through game use?
Studying games as artifacts in and of themselves
(e.g. affordances of the medium, critical analysis, rhetoric)
3. Industry and engineering approach
Understanding the design and development of games
(e.g. how to make better games)
Games as drivers of technological innovations
(e.g. graphics, AI, networking, etc.)
Game Attributes
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Gameplay
Aesthetics
Harmony
Storytelling
Risk & reward
Novelty
Learning
Self-expression
Immersion
Games & AI
• Arthur Samuel’s Checkers Games (c. 1950) at IBM.
Introduced rote learning (the software could learn
from multiple iterations of the game).
• IBM’s Deep Blue defeats Gary Kasparov (world chess
champion) in 1987.
• IBM’s Watson defeated 2 human players of Jeopardy!
in 2011.
AI
• Rule-based systems, such as behaviors of game
objects (such as NPC’s, or Non-Player Characters)
• Pattern recognition
• Natural Language Processing