Rule 2: Two points are adjacent if they are next to each other in a vertical or horizontal but not diagonal direction. Two stones of the same colour on adjacent points are connected and belong to the same string of stones. An empty point adjacent to a string of stones is a liberty of that string. When a stone is played that reduces one or more strings of the opponent's stones to 0 liberties (in other words, when it surrounds opposing stones), those strings are captured and removed from the board.
In Figure 1 below, the two stones marked "A" are on adjacent
points and they are connected together. So are the two stones marked "B".
But the two stones marked "C" are not on adjacent points and they
are not connected. Much longer strings of connected stones are often formed.
For example, all of the stones marked "D" are connected together,
and so are all of the stones marked "E". But these two strings
of stones are not connected to each other, even though they are close together.
Figure 1: Connected Stones
Each vacant point adjacent to a string of connected stones is a liberty
of those stones. A single stone in the centre of the board (like A in Figure
2, below) has 4 liberties, as shown. A stone on the edge of the board (B)
has 3 liberties, and a stone in the corner (C) has only 2. The stones marked
"D" are already partly surrounded by enemy stones, and they have
only 4 liberties left. Question: How many liberties do the stones marked
E and F have? (Click here to check your answer.)
Next Page | Previous Page | Contents | My Go Page | My Home Page