This site now hosts a complete archive of PDF versions of The Problemist Supplement, from 1992 to the current year. This magazine is aimed mainly at newcomers to chess composition, so it is recommended for those who want to find out more about chess problems. You can find the archive here.
White is to play and mate in two moves. Have a go at solving this first and then, when
you are ready, click the button below to see the solution and a commentary explaining
what the problem is all about.
A good chess problem only uses force that is necessary. A brief glance at the
diagram tells us that wPg2 is out of play. Consequently we can ”solve“ this
twomover at a glance! 1.Bh2! (>2.g4) This feeling is reinforced when we notice
that any move by bSf4 defends by opening the line of bRd4. However, the line of wBh2 is
opened to e5 and this clearly affords potential! The solving process is not just about
finding the key but there is enjoyment to be had in unravelling the play, which in this
instance is most complex! Let us first consider any random move of bSf4; 1...Sfxg6
appears strong but, as wBh2 now holds e5, 2.Sxd4 reclaims e6! Specific moves by bSf4
attempt to prevent this mate. 1...Se2 guards d4 but interferes with bRe1 to permit
2.Sxe7, another mate dependent on the changed control of e5. 1...Se6 likewise also
guards d4 and also interferes with bRe1... but 2.Sxe7? is not mate. Black has unpinned
his own bQd7! However, 1...Se6 additionally interferes with bBa2 to enable 2.Qf7#.
Finally 1...Sfd5 prevents 2.Sxd4 by unpinning bPc5. This defence also interferes with
bBa2 but prevents 2.Qf7? by arranging an interposition on f6. It is the interference
with bRd4 that determines the mate, 2.Sd6#, and in this way the function of the last
white piece is decided. The final roll call of mates might be summarised thus:
1...Sf~/Se2/Se6/Sfd5 2.Sxd4/Sxe7Qf7/Sd6. The bSf4 is said to correct the error of its
random move in a number of different ways. You may have noticed two reasons for the
correction 1...Se6. Not only does the bS guard d4 but it also unpins the bQ to pre-empt
2.Sxd4. The motivation for this defence is regarded as impure. In complicated problems
it is often impossible to ensure a unique motivation for the moves.