The basis of gambling theory is uncertainty. Nobody wins money by betting on an outcome which is certain to occur, unless the other party to the wager is stupid or misinformed. When A bets B at level stakes that event E will occur, he is backingh his judgment that E is more likely to occur than not. He may base his opinion on knowledge or guess work. The wager is only possible because B, having also based his opinion on knowledge or guesswork, has come to an opposite conclusion.

A bettor on a horse race might be backing his knowledge of the form and peculiarities of the horses and jockeys engaged in the race. A man who wants to gamble for the sake of it might bet, for example, that the next throw of a true diewill result in a 6 being thrown. His opinion is based only on guess work, since there are no grounds for believing that a 6 is more or less likely to be thrown than any other number.

Whatever his method, each of the bettors will have either a good or a bad bet. The first man will have a good bet if he accepts odds of 20-1 about a well-fancied horse in a field of eight, or a bad bet if he accepts 2-1 in an open handicap with a large field. The second man will have a good bet if he accepts odds of more than 5-1 and a bad bet if he accepts less. His chances can be precisely calculated in gambling theory.

The ability to calculate chances is of prime importance to the gambler and gambling theory. It might be thought that, since the outcome of a chance event by definition cannot be predicted, it must occur in a sense accidentally, and can obey no laws. However, the theory of probability and the law of large numbers give indications of the outcome of chance events. They should not be underrated as they are the necessary foundations for much of the most advanced theories of science. The theory of probability was first studied and defined by mathematicians in connection wit hproblems of gaming. It is now the basis of commercial businesses like insurance, and essential to all branches of physics, chemistry, astronomy and the exploration of space.

Games upon which money is wagered fall into three categories: skill games, games of chance and games where both skill and chance play a part. Games of skill are not necessarily more complex than games of chance. The child’s cardgame called snap is a game of pure skill, as a player has nothing but his own ability to help him win. Noughts and crosses is also a game of skill. Two good players will draw every game they play. Bridge and poker are cardgames in which both skill and chance play a part. Poker players assert that poker is the more skilfulgame as the best players win more consistently. Most casino games are games of chance.