Responsibility and Choice

As a teenager, one of the most thought-provoking paragraphs I read in a fantasy story was something The Master Summoner tells Ged:

You thought, as a boy, that a mage is one who can do anything. So I thought, once. So did we all. And the truth is that as a man’s real power grows and his knowledge widens, ever the way he can follow grows narrower: until at last he chooses nothing, but does only and wholly what he must do...
   - Ursula Le Guin, A Wizard of Earthsea, Chapter 4

Yesterday I was surprised to read a very similar sentiment in one of the Amber novels:

It seemed that a balance had shifted somewhere along the way, and that I was no longer acting but being acted upon, being forced to move, to respond. Being herded. And each move led to another. Where had it all begun? Maybe it had been going on for years and I was only just now becoming aware of it. Perhaps we are all victims, in a fashion and to a degree that none of us had realized.
   - Roger Zelazny, Sign of the Unicorn, Chapter 3