If you’ve ever seen a domino rally, a long line of hundreds or even thousands of dominoes set up in careful sequence to topple with the nudge of just one, you’ve probably been impressed by the visual spectacle. Domino builders compete in domino rallies to see who can build the longest and most imaginative chain of reactionary dominoes before an audience of fans. While it’s not quite as satisfying to watch a domino rally in real life, it is possible to use the concept of a domino effect to help you plot a novel.
A domino is a small rectangular wood or plastic block, usually twice as long as it is wide, with an arrangement of dots, resembling those on dice, on the face and either blank or marked with a number, or a combination of numbers, on each side. The number of dots on a particular piece identifies its value, or rank. A domino with all its pips visible is said to be “full”; it has the most rank and power, while a domino with all its pips covered or concealed is called a “blank” or “empty.”
The word domino comes from the Latin for “little crown,” and was originally used to denote a type of hooded cloak worn together with a mask at carnival season or during a masquerade. By the late 18th century, however, domino had become a common name for the game of laying them edge to edge against each other so that their exposed ends match or form some specified total. Larger sets of dominoes may also be arranged so that the values on both the exposed and hidden ends are equal, so that a domino with six pips on each end is counted as two, and a domino with three pips on each end as one.
In addition to their logical uses, dominoes are also popular for games in which players try to score as many points as they can by laying them in a row. In a simple game, each player starts by placing a domino so that the open ends of the tile touch one another (one’s to the right of the other’s), then places a second domino so that the two exposed sides are identical. Then each player scores the points on the opposing player’s exposed tiles—if there are a six to one side, a domino with a 6-6 counts as 6, and so on.
In fiction, the domino effect is a way of showing how actions impact subsequent ones. It’s important to use this concept when writing scenes, especially when the action is outside a character’s usual sphere of influence. For example, if your hero goes against the law to solve a mystery, you need to give readers enough logic for them to keep liking him or forgive his transgressions. Unless you write a story with the logic of a domino cascade, readers will lose interest.