LotR -- Book 4 - Chapter 10 - The Choices of Master Samwise

[Kuruharan]

finally he is overwhelmed by an external power too great to be withstood. His selfhood is gradually broken down by these external powers making use of him for this 'greater good'. Yes, he agreed to take the Ring to the Fire, but did he agree in full knowledge of what he would become?

Hmm, well...that is a difficult question. Judging from some of the things Gandalf said it would appear that Frodo did not. However, Gandalf also gives the impression that Frodo would have carried on anyway.

Not all the powers working on him were working for the greater good. I still think that his acceptance of the Quest implies a degree of consent to being temporarily dominated by things like the Phial if his life and Quest were in jeopardy.

I sense much potential for discussion fodder in the Mount Doom chapter.

that evil si ultimately self defeating, & brings its destruction on itself. Good doesn't win out because its more powerful but because evil contains the seeds of its own destruction.

But since Good does not self-destruct, doesn't that make it more powerful?