In a changing world, some things do not change. It may be fashionable to decry the simple Virtues, but we still like to find them in our friends. Loyalty, honesty, frankness, gratitude, chivalry, magnanimity – these are the hallmarks of the good friend, the good husband and father, the nice guy we all hope our daughters will marry.

In the amoral world of Diplomacy, however, they are the hallmarks of the born loser. If a fallen enemy reaches out a hand for assistance, the wise man lops it off. If a friend does you a good turn when you’re down, wait until he’s down, then beat him to death. If an ally asks for your help in planning the next season’s moves, give it freely and copiously, then do the reverse of what you agreed and let him take the counter-attack. Try to surround yourself with people who trust you, then let them down; find an ally who will gladly die for you and see that he does just that.

In short, Diplomacy is not a nice game; to win, it is necessary to behave like a complete cad. Some people adopt a tone of moral outrage at the philosophy of the game, and refuse to play it at all: though it is already unfashionable, and will soon no doubt be illegal, to acknowledge any difference between the sexes, this attitude is particularly common among women — a cynic might say that Diplomacy threatens to erode the natural advantage their innate duplicity gives them over men in real life. At any event, this moral posture is quite untenable. We all have these anti-social tendencies somewhere within us, and it may be better to give them free rein in a harmless game, suppressing them where they could do real damage.

Not a nice game, as I said; but a marvellously entertaining one. Of all the countless board-games that have followed in the wake of Monopoly, none has acquired the devoted cult-following of Diplomacy: a game of pure skill for seven pedigree rats with time on their hands.