Introduction to Strategy
The rules stipulate that the winner of an Othello games is the player who has the most discs of his colour at the end of the game. Newcomers to the game too often have the tendency to transform this long-term objective into a short-term tactic : they try to have the most discs at each stage of the game. To do this, they play at each move the move which turns the greatest number of discs possible. This is called the maximum disc strategy. Fortunately for the game's interest, after several games against an experienced player, one clearly sees that this strategy is not good, as we will try to demonstrate with an example.
Maximum Disc Strategy
In diagram 1, black has only one disc with only four moves to go. Surely white has a certain win?
Black may play a1 or h8, and in this manner, he may play all the remaining moves (since white must pass after each move), for a final score of 40-24 for black! It's therefore clear that having lots of discs, even very close to the end of the game, does not absolutely guarantee an ultimate victory. In the example of diagram 1, white indeed has many discs, but they are vulnerable : they can be flipped back by the opponent. What's important is therefore not to have many discs but rather to have many discs which can not be flipped back by the opponent, no matter what happens for the rest of the game. Such discs are called "stable discs". Of course, it's often very difficult to acquire stable discs before the last few moves of the game; but first let's see some examples of stable discs.