Lesson 8 of 12
Life and death
3 min

False Eyes in Go: Why Some Eyes Don't Count

An empty point inside your stones is only an eye if every stone around it belongs to one group. When they don't, the opponent can cut them off and then take them by playing inside. You play Black.

Step 1 of 4

An eye that isn't
Black's group seems to have two eyes, A9 and D9. But White's stone on C8 cuts D8, E8 and E9 off from the rest: they touch the other black stones only through D9, so D9 is their last liberty. White plays there and takes them. D9 was a false eye. The rest of Black's group is left with one eye, A9, and it dies too.
Make the eye real
The same group before White got to C8. Now C8 is empty, and whoever plays there decides whether D9 is an eye.
Your move
Make your group live with two real eyes.
One diagonal is not enough
Away from the edge, an eye has four diagonal points. Here White holds one of E5's four, F6. Is E5 a real eye?
Question
Make White's eye false
White's group on the top edge has room for two eyes: F9, and the space at H9 and J9. If White plays G8, both are real and the group lives. Find the move that leaves White one real eye.
Your move
Kill White's group.

What you learned

An eye is real only if the stones around it are one group, or can't be cut apart.
On the edge or in the corner, one opponent stone on an eye's diagonal makes it false. Away from the edge it takes two.
Mend a false eye by taking the point that joins its stones.
To kill, take that point first, and the eye is false.