Intro:
Before you begin
Step 1:
Learn the fuseki
Step 2:
Learn to make groups
Step 3:
Learn to capture
Step 4:
Avoiding the ladder
Step 5:
Avoiding suicide
Step 6:
Using eyes
Step 7:
The ko rule
Step 8:
Ending and scoring the game

2torial #0589:
Learn2 Play Go (continued)

Using eyes

Eyes can either make a group very vulnerable, or invulnerable. Below is an example of of the first kind, when a group has only one eye and no other liberties. If this happens, it's possible to capture all the group's stones:

A. On the left, the X marks the white group's eye. White still has another liberty, which is marked by the star.

B. In the next graph, black plays in the liberty marked by the star. This move destroys the last playable liberty of the white group.

C. In the third graph, you can see that when black plays the white group's eye, it closes off the group's last liberty and thereby captures the entire group.

D. The last graph shows what that section of the board looks like after the white stones are removed.

However, if a group has two eyes separate in the group (not on adjacent intersections), it's safe from attack. As a comparison, look at the two diagrams below.

A. The black group has two intersecting eyes. To capture, white simply needs to play one of the eyes, let black play the other to capture, and then white can play the remaining eye (left open when its stone was removed) and take black's group.

B. White can't play either of the eyes. To do so would be suicide.

Step 7