Go life and death: two eyes
A group with two separate eyes can never be captured. Learn what an eye is, and practise finding the vital point that makes two. Life, death and tactics · lesson 2 of 5.
The lesson in words
An eye is an empty point inside your group that the opponent can’t fill: a stone played there would have no liberties.
A group with two separate eyes can never be captured. White would need to fill both at once, and it only gets one move.
Your group in the corner has a space of three points. Right now it’s one big eye. White could play in the middle and kill it.
Try it: Play the vital point to make two eyes.
Two eyes means alive forever. Next: the ladder, a capture that runs across the board.
Questions
Why can’t white capture a group with two eyes?
Each white stone in an eye would have no liberties and capture nothing, so it’s suicide. Both eyes would have to be filled at once.