Tablebases

t. In 1977, Thompson showed up at the World Computer Chess Championship th a new creation, a database that played the king and queen versus king and rook endgame perfectly. (KQKR is the abbreviation.) It wasn'1 an engine; there was no thinking required. Thompson had generated a database that essentially solved chess backwards, what we call retrograde analysis. It started from checkmate and worked its way back until it contained every single possible position with that material balance. Then i...