An elderly man was sitting alone on a dark path, right? He wasn't certain of which direction to go, and he'd forgotten both where he was traveling to and who he was. He'd sat down for a moment to rest his weary legs, and suddenly looked up to see an elderly woman before him. She grinned toothlessly and with a cackle, spoke: 'Now your third wish. What will it be?'
'Third wish?' The man was baffled. 'How can it be a third wish if I haven't had a first and second wish?'
'You've had two wishes already,' the hag said, 'but your second wish was for me to return everything to the way it was before you had made your first wish. That's why you remember nothing; because everything is the way it was before you made any wishes.' She cackled at the poor berk. 'So it is that you have one wish left.'
'All right,' said the man, "I don't believe this, but there's no harm in wishing. I wish to know who I am.'
'Funny,' said the old woman as she granted his wish and disappeared forever. 'That was your first wish.'
-- Dialogue from Planescape: Torment
this made me smile, thanks!
Nice. For anyone who hasn't played the game, the answer to the riddle (the title of this post) is "regret."
An alernative solution to the riddle would be A Witch.
Actually, the answer isn't *only* regret. The Nameless one himself says:
"If there is anything I have learned in my travels across the Planes, it is that many things may change the nature of a man. Whether regret, or love, or revenge or fear - whatever you *believe* can change the nature of a man, can. I’ve seen belief move cities, make men stave off death, and turn an evil hag's heart half-circle. This entire Fortress has been constructed from belief. Belief damned a woman, whose heart clung to the hope that another loved her when he did not. Once, it made a man seek immortality and achieve it. And it has made a posturing spirit think it is something more than a part of me."
The answer sounds more like Belief. Belief can change a man.