# Capture three to make an eye

Difficulty: Beginner   Keywords: Life & Death, Proverb

 Table of contentsCapturing three stones suffices to make an eye Exceptions Heuristic

### Capturing three stones suffices to make an eye

An example at the edge of the board.

Capture three to make an eye

When White captures at ...

Capture three to make an eye

...even when Black throws in with , White can make a second eye with .

This works away from the edge, too.

Capture three to make an eye

Capturing three White stones at makes an eye too, so Black lives.

### Exceptions

However, this proverb has exceptions too.

Exception

In this case, despite capturing three Black stones at ...

Exception

... kills. Since a and b are miai, White dies.

Here is another counter-example. Such an counter-example can also be found away from the side.

Exception

If Black captures the three stones with , then...

Exception

... recaptures. Because of and the eye around a is a false eye.

### Heuristic

A possible heuristic to see whether the "capture three to make an eye" proverb applies is to look at the position immediately after capturing. In each of the four cases below, we see whether we can form an Black eye at either the a points. If White can occupy all the b points after Black's capture, then Black has no eye here.

Heuristic for corner.
Heuristic for side.
Heuristic for side.
Heuristic for center.
Heuristic for center.

A related page is capture two recapture one.