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What Is a 'Liberty' in Go? Counting Breath, Simply

Read ~6 min · Updated July 2026 · Part of: Learn Go

If you can only understand one concept in Go, understand liberty (氣). It's the single rule that runs through the entire game — capture, life and death, everything grows out of it. Get liberty, and the rest is detail.

English中文Plain meaning
liberty氣an empty point orthogonally adjacent to a stone — its breath
group / string一群子same-color stones connected orthogonally; they share liberties
atari打吃down to one liberty, about to be captured
capture提子／吃子fill the last liberty → remove the stones

1. A liberty is a stone's "breath"

A liberty is an empty point orthogonally adjacent (up/down/left/right, not diagonal) to a stone. Each empty neighbor counts as one liberty — think of it as one breath.

Fill in every empty point around an enemy stone, and it runs out of liberties — so it's captured and removed. That's the entire capture rule, in one sentence.

🫁 Analogy: picture a stone as a swimmer. Liberties are its breath. Plug every gap around it and it drowns — removed from the board.

2. A concrete demo: out of liberties means captured

See it directly. Here's an entry-level position from the brainGO engine — the white stone has one liberty left, and Black captures it in 1 move:

Count liberties: White (0,0) — its orthogonal neighbors are (0,1), a black stone (not empty, not a liberty), and (1,0), an empty point (one liberty). So white has exactly 1 liberty. Black plays (1,0), fills it → white drops to 0 → captured. Liberties go from 1 to 0 and you're out — that's the whole math.

🔬 This "1-move capture" is verified by the brainGO engine at build time: Black can capture (0,0) in one move, the solution is unique.

3. Single-stone liberties: four positions

A lone stone's liberty count depends on where it sits:

Stone position Liberties Mental picture
Center (e.g. 1,1) 4 air on all four sides
Edge (e.g. 0,1) 3 one side is the board edge, no air there
Corner (e.g. 0,0) 2 two sides are edges, only two liberties

→ Corners are the most fragile (only 2 liberties), which is why beginners lose stones in corners — fill one and it's atari. This position-vs-liberty table is the foundation of the atari counting table.

4. Groups share liberties (the key idea)

Two or more same-color stones connected orthogonally form a group. The group's liberties = all empty points touching any stone in the group (counted once, not per-stone).

🐋 Analogy: one swimmer has one pair of lungs; a chain of hand-holding swimmers shares the air around the whole chain — to capture them you have to cut off the whole group's air at once, not one by one.

How to count a group's liberties:

  1. Identify the whole group (all same-color stones connected orthogonally).
  2. Look at every neighbor of the entire group.
  3. Only empty points count (opponent stones and your own stones don't).
  4. The same empty point touched by several group stones counts once (no double-counting).

Example: two connected black stones in the center have 6 empty neighbors around them → the group has 6 liberties (not 4+4=8, because the touching point is shared).

This is why "connecting" is often a defensive move: connected stones usually have more combined liberties than scattered ones, and can only be captured together (you have to fill the whole group's liberties at once).

5. Atari: the one-liberty alarm

A group down to one liberty is said to be in atari. That's Go's fire alarm: the opponent can fill that liberty next move and capture the whole group.

🔔 The reflex to build: when your own stones drop to one liberty, immediately ask "can I extend (give them more liberties next move), or do I abandon them?" When the opponent is in atari, ask "can I fill that liberty right now?"

6. The 4 most common liberty-counting mistakes

  1. Diagonals aren't liberties. Two stones touching only diagonally are not one group and don't share liberties — each counts independently. Beginners often misread diagonal as connected.
  2. Double-counting liberties. A group shares liberties — the same empty point counts once. Don't add up each stone's liberties (you'll double-count).
  3. "Looks surrounded" ≠ captured. Don't go by feel — count empty neighbors. As long as there's one empty orthogonal neighbor, it's alive.
  4. Forgetting your own stones don't count. Your own stones occupying a neighbor don't add liberties (but same-color connected stones form one group that shares outer liberties).

7. How liberties run through the whole game

Liberty isn't just one capture rule — it's the foundation of everything:

So getting fluent at counting liberties is installing Go's core engine in your head.

How to train it

Counting liberties from a static diagram is the slow way. The fast way: puzzles where you "fill the last liberty" to capture, with instant feedback — that's what capture-go training is for.

👉 Play brainGO — fill the last liberty

FAQ

Do diagonally-touching stones count as one group and share liberties?

No. "Connected" in Go means orthogonal (up/down/left/right) only — diagonals don't count. Two stones touching only diagonally are separate groups, each counted on its own.

How do you count a group's liberties?

Identify the whole group (same-color, orthogonal) → look at all neighbors of the entire group → only empty points count → an empty point touched by several group stones counts once. In short: "count the empty points around the whole group," no double-counting.

Why does a corner stone have only two liberties?

A corner stone has the board edge on two sides (no points, no liberties), leaving only two. Edges have 3, the center has 4. So corners are the most fragile, and that's where beginners lose stones.

Are liberties and "eyes" the same thing?

No. A liberty is "an empty point next to a stone" (a breath); an eye is "an empty point surrounded by your own stones." An eye is a special kind of liberty — a group with two eyes has liberties that can never be filled, so it lives forever.

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