GO LIBERTIES AND CAPTURES — ORIGINAL PRACTICE RECORD Complete 5 x 5 boards; A-E left to right, 1-5 bottom to top. B=Black, W=White; all unlisted points empty. No self-capture after opposing captures; Exercise 12 uses immediate simple ko only. Source: https://www.britgo.org/intro/intro2.html BLANK REVIEW Exercise / target string: Original occupied coordinates / proposed move: Distinct liberties before: Opposing strings with zero liberties after trial: Captured coordinates removed: Own string and liberties after removal: Repetition convention / supplied previous position: Accepted or rejected / resulting board: Extra or missing coordinate in my first answer: EXERCISE 1: A centre stone Black: C3 White: Count the liberties of Black C3. Write the coordinates before writing a number. Does an empty diagonal point add another liberty? My coordinate list / accepted board: ____________________ EXERCISE 2: A side stone Black: A3 White: Count Black A3 on the left side. Is there a fourth liberty outside the printed board? My coordinate list / accepted board: ____________________ EXERCISE 3: A corner stone Black: A1 White: Count Black A1 in the lower-left corner. Which two directions end at the board edge? My coordinate list / accepted board: ____________________ EXERCISE 4: Diagonal contact is separate Black: B2, C3 White: Black B2 and C3 touch diagonally. Are they one string? Count B2, then count C3 separately. My coordinate list / accepted board: ____________________ EXERCISE 5: A connected pair Black: B2, C2 White: B2 and C2 touch along a line. Count the liberties of the entire black string. Why is adding four plus four wrong? My coordinate list / accepted board: ____________________ EXERCISE 6: Count a shared liberty once Black: B2, B3, C2 White: Count the L-shaped black string. C3 touches both C2 and B3: does that make it two liberties? My coordinate list / accepted board: ____________________ EXERCISE 7: Take the last liberty Black: B3, C2, C4 White: C3 White C3 has one liberty. Black proposes D3. Which stone is removed, and how many liberties does the newly placed black stone have afterwards? My coordinate list / accepted board: ____________________ EXERCISE 8: Remove the whole string Black: B3, B4, C2, C5, D3 White: C3, C4 White C3–C4 is connected. Black proposes D4. List every removed stone and recount the black D3–D4 string. My coordinate list / accepted board: ____________________ EXERCISE 9: Capture before checking your own liberties Black: A3, B2, C1 White: A2, B1 A1 initially touches White A2 and B1 with no empty neighbour. Is Black A1 self-capture, or does capture make it legal? My coordinate list / accepted board: ____________________ EXERCISE 10: A prohibited self-capture Black: White: B3, C2, C4, D3 Black proposes C3 between four white stones. Does the placement capture any white string, and may it remain on the board? My coordinate list / accepted board: ____________________ EXERCISE 11: An occupied destination Black: B3, C2, C4 White: C3 Black proposes placing directly on White C3. Can the player remove that white stone and put Black there? My coordinate list / accepted board: ____________________ EXERCISE 12: The immediate ko recapture Black: B3, C2, C4 White: C3, D2, D4, E3 Black plays D3 and captures White C3. On the very next turn White proposes C3. Compare the proposed result with the complete board before Black’s move. What does the simple-ko convention prohibit? My coordinate list / accepted board: ____________________ ANSWER KEY — open after writing your own record 1. Black C3 has four liberties: B3, C2, C4 and D3. Each is empty and touches C3 along a line. B2, B4, D2 and D4 are diagonal and do not count. All other intersections are empty, but a distant empty point is not a liberty of this stone. This is a local count, not a claim about territory or the final score. Start every exercise by naming the target stone or string; otherwise a correct-looking total can refer to the wrong object. 2. The three liberties are A2, A4 and B3. The board ends at file A, so there is no intersection to the left of A3. Do not imagine a stone or an empty point beyond the edge. The same side rule applies on the top, bottom and right edge. If another stone later occupies one of these three points, recount the position actually shown. Fewer empty neighbours at the edge does not by itself decide whether a move is strategically good. 3. Black A1 has two liberties, A2 and B1. Below rank 1 and to the left of file A there are no board points. B2 is diagonal, so it does not supply a third liberty. This corner is part of the complete five-by-five exercise board, not a cropped view of a larger board. That distinction matters: a crop would need additional edge information before its count could be trusted. Here all four edges are real and every occupied intersection is listed. 4. They are two separate strings. B2 has A2, B1, B3 and C2; C3 has B3, C2, C4 and D3. Each therefore has four liberties. B3 and C2 occur in both lists because an empty point can be adjacent to separate strings. That overlap does not connect the stones and does not let one stone borrow all the other string’s liberties. Keep the target lists separate. If a later legal move connects them, start a new count on the resulting connected string. 5. The connected pair has six liberties: A2, B1, B3, C1, C3 and D2. B2 and C2 are occupied, so their shared boundary does not contain an empty liberty. Follow the whole string and collect its adjacent empty coordinates. The two stones are captured together only if that combined liberty set becomes empty. A string is not counted by adding the empty-board neighbour total of each member; doing that ignores occupied points and, in other shapes, can count the same empty intersection twice. 6. There are seven distinct liberties: A2, A3, B1, B4, C1, C3 and D2. C3 appears once, even though it touches two stones in the same string. The target is the complete connected set B2, B3 and C2. A useful hand method is to write each empty neighbour and cross out repeated coordinates before counting. The answer is a set of board points, not a count of stone-to-point contacts. This is why a longer string cannot be judged reliably from stone count alone. 7. Before the move, White C3 has only D3; B3, C2 and C4 are black. Black D3 fills that last liberty, so White C3 is removed. Recount after removal: Black D3 has C3, D2, D4 and E3, four liberties. C3 is now empty and can be counted. Black does not move onto C3 to perform the capture; the new stone stays at D3. The three other black stones are not orthogonally connected to D3 in this particular position. A one-stone capture does not establish the result of a whole game. 8. D4 is the white string’s only liberty. C3 and C4 belong to one string, so both are removed when Black fills D4. The resulting black D3–D4 string has six liberties: C3, C4, D2, D5, E3 and E4. Two newly emptied points appear in that list. Remove the whole captured string before counting Black’s liberties; leaving one white member on the board would create a different, incorrect position. The other black stones remain where they were. This exercise checks capture mechanics rather than a preferred attacking plan. 9. Black A1 is legal in the stated no-self-capture convention because it first captures White A2 and B1. Each white stone is a separate string whose only liberty is A1. Remove both after the placement. Black A1 then has the two empty liberties A2 and B1. Checking the newly placed stone before resolving opposing captures would reject this move incorrectly. The two captured stones need not be connected to each other. This is a complete corner position; the black stones A3, B2 and C1 supply the surrounding occupation shown. 10. It captures no white string: each neighbouring white stone has other empty liberties. Black C3 would then have no liberty and is not connected to another black stone with liberties. Under this worksheet’s no-self-capture convention the move is prohibited. The final accepted board remains the starting board, with C3 empty. Do not keep the trial stone or remove a white stone merely to make the move work. Other rule conventions need their own explicit statement; this answer applies to the one named for these exercises. 11. No. C3 is occupied, so Black may not place there. Capturing in Go occurs by legally placing on an empty intersection and removing opposing strings whose last liberty is filled. In the starting position, D3 is the empty last liberty of White C3, as shown in Exercise 7. The rejected proposal at C3 changes nothing: White C3 remains and no black stone is added. Checking vacancy comes before calculating captures or discussing whether a move looks useful. A capture is not a move onto an opponent’s stone. 12. Black D3 captures C3 and has C3 as its sole liberty. A trial White C3 would capture D3 and restore exactly the board shown before Black’s move. The supplied history is therefore enough to identify the immediate repetition: simple ko prohibits that immediate recapture. The accepted board after the rejected proposal is still the board after Black D3. Do not call every one-stone capture ko; both the shape and the prior position matter. This exercise teaches that specific prohibition and does not adjudicate a longer repetition sequence under a superko rule.