Morton's Fork describes a choice between two equally unpleasant alternatives, or two lines of reasoning 
that lead to the same unpleasant conclusion.

Cardinal Morton, Chancellor under King Henry VII, habitually extracted taxes from wealthy London merchants
for the royal treasury.  His approach was that if the merchants lived ostentatiously, they obviously had 
sufficient income to spare for the king.  Alternatively, if they lived frugally, they must have substantial
savings and could therefore afford to contribute to the king's coffers.  In either case they were 
impaled on "Morton's Fork". 

Familiar to bridge players as the "Morton's Fork Coup"; I suspect chess players know this as well, if perhaps 
under a different name. -- JohnWebber

''Well, there's the "knight's fork", wherein a knight attacks two pieces simultaneously and the victim must give up one to save the other.  Then there's "zugzwang", which is where you're in an OK position, but it's your move, and any move you can make will leave you worse off.''