The table assumes that the board is open for every possible throw. If part of the throw is blocked by an intervening point being held by adverse men, the chance of being hit may be less. Thus, a blot may be hit on an eight with dueces ; fours ; cinque, trois (twice) ; or six, deuce (twice). If the fourth point is blocked, the blot cannot be hit with deuces or fours, and consequently the chance of its being hit is reduced from 30 to 6 to 32 to 4, or from 5 to 1 to 8 to 1.
Two principles, then, have to be considered in moving the men : (1.) To make points where there is the best chance of obstructing the opponent; (2.) When obliged to leave blots, to choose the position in which they are least likely to be hit, i.e., either as near as possible to an adverse man, or as far as possible from any adverse men ; or where the intervening points are blocked by the player's own men.
At the beginning of the game it is advisable, if possible, to secure the cinque point in your own inner table, or the cinque point in your adversary s inner table, or both. If you succeed in this, you should then play a bold game in hopes of winning a gammon. The next best point to gain is your own bar point ; and the next to that the quatre point in your own inner table.
If you are fortunate enough to secure all these points, and your adversary s inner table is less favourably made up, it is then to your interest to open your bar point (in expectation of compelling your adversary to run out of your inner table with a six), and also to keep any men you may have in the outer tables spread (i.e., not to crowd a number of men on one point). In this case you have a good chance of hitting the man your adversary brings out, and also of hitting the man he has left on your ace point.
If you succeed in taking both these men, and your adversary has a blot in his inner table, it will be to your interest not to make up your own table, but to leave a blot there on purpose, in hopes of his entering on it. You will then have a probability of hitting a third man, which, if accomplished, will give you considerable odds (according to Hoyle, 4 to 1) in favour of winning a gammon; whereas if you have only two of his men up, the odds are against your gammoning him.
The best move for every possible throw at the commencement of a game is as follows : If you throw aces (the best of all throws), move two on your bar point and two on your cinque point. This throw is often given to inferior players by way of odds.
Ace deuce : move the ace from your adversary s ace point (if playing for a hit only), and the deuce from the five men placed in your adversary s outer table. If playing for a gammon, move the ace from the six to the cinque point in your inner table.
Ace trois : make the cinque point in your inner table.
Ace quatre and ace cinque : move the ace from your adversary s ace point, and the quatre or cinque from the five men in your adversary's outer table. If playing for a gammon, play the ace on the cinque point in your inner table.
Ace six : make your bar point.
Deuces : move two on the quatre point in your inner table, and two on the trois point in your opponent s inner table. If playing for a gammon, move two on the quatre point in your inner table, and two from the five men in your adversary s outer table.
Deuce trois and deuce cinque : move two men from the five placed in your adversary s outer table.
Deuce quatre : make the quatre point in your own table.
Deuce six : move a man from the five in your adversary s outer table, and place him on the cinque point in your own table.
Threes : play two on the cinque point in your inner table, and three on the quatre point of your adversary s inner table. For a gammon, play two on your cinque point and two on your trois point in your inner table.
Trois quatre : move two men from the five in your opponent s outer table.
Trois cinque : make the trois point in your own table.
Trois sir : bring a man from your adversary s ace point as far as he will go.
Fours : move two on the cinque point in your adversary s inner table, and two from the five in his outer table. For a gammon, move two men from the five in your opponent's outer table to the cinque point in your own table.
Quatre cinque and quatre six : carry a man from your adversary s ace point as far as lie will go.
Fives : move two men from the fire in your adversary s outer table to the trois point in your inner table.
Cinque six : move a man from your adversary s ace point as far as lie will go.
Sixes (the second best throw) : move tro on your adversary s bo.r point, and two on your own bar point.
Subsequent moves depend on the intervening throws ; consequently the problem becomes too complicated for analysis. Some general rules, however, may be given.
In carrying the men home carry the most distant man to your adversary's bar point, next to the six point in your outer table, and then to the six point in your inner table. By following this rule as nearly as the throws admit, you will carry the men to your inner table in the fewest number of throws. "When all are home but two, it is often advisable to lose a point, if by so doing you put it in the power of a high throw to save a gammon.
If, in endeavouring to gain your own or your adversary s cinque point, you have to leave a blot and are hit, and your adversary is forwarder in the game than you, you must put another man on your cinque or bar point, or into your adversary s table. If this man is not hit, you may then make a point, and so get as good a game as your opponent. If it is hit, you must play a back game (i.e., allow him to take up as many men as he likes) ; and then in entering the men taken up, endeavour to secure your adversary's ace and trois points, or ace and deuce points, and keep three men upon his ace point, so that if you hit him from there you still keep the ace point protected.
To find which is the forwardest, reckon how many points you have to bring all your men home to the six point in your inner table. Add to this six for every man on the six point iu your tables, five for every man on your cinque point, and so on ; and then make the same calculation for your adversary's men.
Avoid carrying many men upon the trois or deuce point in your own tables, as these men are out of play, and the board is left open for your adversary.
Whenever you have taken up two of your adversary s men, and have two or more points made in your inner table, spread your other men to take the best chance of making another point in your tables, and of hitting the man your adversary enters. As soon as he enters, compare his game with yours, and, if equal or better, take up his man, except when playing for a hit only, and your playing the throw gives you a better chance for the hit.
Always take up a man if the blot you leave in making the move can only be hit with double dice, except when playing for a hit only, and you already have two of your opponent's men in your tables, and your game is forwardest; because your having three of his men in your tables gives him a better chance of hiting you with out leaving a blot than if he has only two.
In entering a man which it is to your adversary s advantage to hit, leave the blot upon the lowest point you can, e.g., ace point in preference to deuce point, and so on ; because this crowds his game by taking out of it the men played on the low point.
When your adversary is bearing his men, and you have two men in his table, say on his ace point, and several men in the outer table, it is to your advantage to leave one man on the ace point, because it prevents his bearing his men to the greatest advantage, and gives you the chance of his leaving a blot. But if, on calculation, you find that you can probably save the gammon by bringing both your men out of his table, do not wait for a blot. To make this calculation, you must ascertain in how many throws you can bring all your men home (a throw averaging eight points), and in how many throws he can bear all his men, on the assumption that he will bear on the average two men at each throw.
The laws of backgammon (as given by Hoyle) are as follows:—
1. When a man is taken from any point, it must be played: when two men are taken from it, they also must be played. 2. A man is not supposed to be played till it is placed upon a point and quitted. 3. If a player have only fourteen men in play, there is no penalty inflicted, because by his playing with a lesser number than he is entitled to, he plays to a disadvantage for want of the deficient man to make up his tables. 4. If he bear any number of men before he has entered a man taken up, and which of course he was obliged to enter, such men so borne must be entered again in the adversary s tables as well as the man taken up. 5. If he have mistaken his throw and played it, and his adversary have thrown, it is not in the choice of either oi the players to alter it, uulc&o they both agree so to do.
