MacHack
MacHack was a chess program that is considered a milestone in the history of computer chess . It was developed from November 1966 by Richard Greenblatt , a student of Marvin Minsky , at MIT .
Greenblatt was inspired by the so-called Kotok-McCarthy Program , a chess program developed at MIT from 1959 to 1962 for the IBM 7090 mainframe. He wrote the first version of the program in just one week and received four hours of computing time a day for tests on the institute's own PDP 6 assigned. As a result, numerous bugs were fixed and additional functions were added; the program was recompiled over 200 times . Greenblatt was offered to write his thesis on chess programming, but it never came about.
The 16 kilobyte program, written in assembly language , could calculate 10 positions per second. Greenblatt implemented 50 heuristics to determine plausible moves. In the first and second half-move of the search 15 moves were examined, in the third and fourth half-move 9 moves. The program usually reached a search depth of five half moves in games. As the first program MacHack had an opening book that contained over 5,000 half moves and was created by Larry Kaufman . In addition, it was able to save 32,000 positions in a hash table and use them to evaluate positions that were created by switching trains. The program's great weakness was in the endgame . Since it valued the importance of the center highly, remote passed pawns were regularly underestimated.
In January 1967, MacHack VI took part as the first chess program in a chess tournament, the Massachusetts Amateur Championship . It scored a five-game draw and received a rating of 1239.
In a demonstration at MIT, the program won a game against Hubert Dreyfus , who is known as a critic of artificial intelligence . Eyewitness Herbert Simon described the event as a "wonderful game between two block pushers " (the English word woodpusher is a common term for weak players).
- Dreyfus - MacHack
- 1. e4 e5 2. Nf3 Nc6 3. Bc4 Nf6 4. Nc3 Bc5 5. d3 0-0 6. Ng5 Sa5 7. Bd5 c6 8. Bb3 Nxb3 9. cxb3 h6 10.Nh3 d5 11. exd5 Bg4 12. f3 Bxh3 13.gxh3 Nxd5 14.Nxd5 Qxd5 15. Bd2 Qxd3 16.b4 Be7 17.Rg1 e4 18.fxe4 Bh4 + 19.Rg3 Bxg3 + 20.hxg3 Qxg3 + 21. Ke2 Qxh3 22.Qg1 h5 23.Bc3 g6 24.Qf2 h4 25. Qf6 Qg4 + 26. Kd2 Rad8 + 27. Kc2 Qxe4 + 28. Kb3 De6 + 29. Qxe6 fxe6 30. Rh1 Rf4 31. Be1 Rf3 + 32. Ka4 h3 33. b5 Rd4 + 34. b4 cxb5 + 35. Kxb5 Ra3 36. Kc5 Rd5 + 37. Kc5 frosted
In the spring of 1967 MacHack won a tournament for the first time a game against a player with a rating . In total, the program played 18 tournament games against human players this year and achieved 3 wins and 3 draws with 12 defeats. It was then made an honorary member of the United States Chess Federation . In 1969, MacHack achieved a rating of 1529.
The program was ported to the faster PDP-10 and was available on several timeshare computers. It took part in chess tournaments until 1972. In 1977 the then otherwise inactive world champion Bobby Fischer played three games against MacHack VI, in which the program had no chance. One of the games went as follows:
- Fisherman - MacHack
- 1. e4 e5 2. f4 exf4 3. Bc4 d5 4. Bxd5 Nf6 5. Nc3 Bb4 6. Nf3 0–0 7. 0–0 Nxd5 8. Nxd5 Bd6 9. d4 g5 10. Nxg5 Qxg5 11. e5 Bh3 12. Rf2 Bxe5 13. dxe5 c6 14. Bxf4 Qg7 15. Nf6 + Kh8 16. Qh5 Rd8 17. Qxh3 Sa6 18.Rf3 Qg6 19. Rc1 Kg7 20. Rg3 Rh8 21. Qh6 mate
literature
- Richard D. Greenblatt, Donald E. Eastlake, and Stephen D. Crocker: The Greenblatt Chess Program (AIM-174) . Massachusetts Institute of Technology, April 1969
Web links
- Bill Wall: Early computer chess programs ( Memento from October 24, 2012 in the web archive archive.today )
- MacHack in the Chess Programming Wiki (English)