RETROGRADE ANALYSIS

A type of chess puzzle in which the challenge is to deduce the previous moves or explain how the position was reached.

Sam Loyd, Musical World, 1859 White plays and mates in 2 moves #2 (2+4) retro

The first need for retrograde analysis appeared in a problem of Sam Loyd, which was published in 1859 in the magazine ‘Musical World’. The solution is as follows: Key : 1.Qa1! ~ (black plays at random) 2.Qh8# Some solvers objected that after the defense 1…0-0-0 (Queen’s side castling) of the Black there is no mate in the second move. The argument of the composer was that Black has no right to defend this way. It is quite obvious from the position of the problem that the previous black move was a move by the King or by the Rook, and that means Black has lost the right for castling.