Sogo

A sogo was an official challenge match during the Edo Era in Japanese go.

When there was a serious dispute such as who should become Meijin it could be settled by a challenge match between the disputants or their representatives. One of the most famous such matches was that between Gennan Inseki and Honinbo Shuwa when Gennan attempted to get himself appointed Meijin Godokoro after Jowa's resignation. The Honinbo house objected and proposed a 20-game match between Gennan and Shuwa. Shuwa won the first game so convincingly that Gennan withdrew his application.

List of Official Challenge Matches

1645-1653 - Honinbo San'etsu vs. Yasui Sanchi: a six-game sogo for the title of Meijin. Played on tagai-sen, Black won all games, resulting in a 3-3 draw. As a result, neither player was promoted to Meijin.

1668-1676 - Honinbo Do'etsu vs. Yasui Sanchi: Sanchi had managed to become Meijin Godokoro by means of political manoeuvering. Doetsu objected, asking for a Sogo. It was granted on the condition that if Doetsu lost he would be exiled forever.

It was a sixty-game affair, with the handicap changing after a lead of six wins or four in succession. The match started on jou-sen, the handicap for a two-rank difference, being Doetsu 7 dan and Sanchi formally the Meijin, i.e. 9 dan.

It seems that the first game ended in Jigo thanks to a previous agreement: this set up the custom to have the first game of a sogo end up in a prearranged jigo.

After 16 games the score was 9-3-4 jigo in Doetsu's favour. The handicap was lowered to sen-ai-sen, but Doetsu won 3 games out of the next four, losing only as white. Sanchi had enough of it; he abandoned the match and resigned as both Meijin and Godokoro.

1737-1740 - Honinbo Shuhaku vs. Inoue Shunseki Inseki: Shuhakus application for promotion to 7 dan was blocked by Hayashi Incho Monnyu (whose application to Meijin had been opposed by the Honinbo and Yasui Houses some time before). Shuhaku challenged Incho to a sogo but the latter refused on grounds of his illness. Shunseki then stepped in to play in his place.

After two and half years only 8 games had been played: Shuhaku was ahead 4-3-1 jigo, but then he suffered a serious stomach haemorrhage. The match had to be suspended. Shuhaku died shortly afterwards, in early 1741.

1766-1767 - Honinbo Satsugen vs. Inoue Shunseki Inseki: a twenty-games sogo to decide the Meijin. After the traditional prearranged jigo in the first game, Satsugen won the next 5 games and applied for a change in the handicap. A series of mutual objections were made by the players regarding the conditions for changing the handicap, until the match was suspended.

Eventually Satsugen was nominated Meijin but wasn't given the post of Godokoro, until 1770 (3 years after end of sogo).

1840 - Shuwa vs. Inoue Gennan Inseki: Gennan's application for Meijin Godokoro was opposed by Honinbo Josaku, who put forward his heir Shuwa for a sogo. Only one game was played though, as Shuwa's 4-point win with black was so convincing that Gennan abandoned the match and rescinded his application.

1842 - Shuwa vs. Inoue Gennan Inseki: Again, only one game was played, Shuwa winning this time by six points. Thereafter, Gennan gave up all hopes to become Meijin.

See Also

• Jubango