from Amber Chronicles by Roger Zelazny:

.."I could be wrong, kid.  I could be very wrong, and if that's the case I apologize for troubling you this much.  On the other hand, it would also be wrong of me not to let you know what the possibility is."
.."What should I do?"..
"No matter what you are and no matter what's been done to you, there will have to be some element of choice for you, sooner or later.  You are greater than the sum of your parts, Merlin.  No matter what went into your birth and your life up to now, you've got eyes and a brain and a set of values.  Don't let anybody bullshit you, not even me.  And when the time comes, if it comes, make damn sure the choice is your own.  Nothing that's gone before will matter then."

"So what might the Pattern or the Logrus want of you?"
"I already told you - a choice of sides."
"Is it that difficult to decide which you prefer?"
"It is that difficult to decide which I dislike less."
"Because they are, as you say, manipulative of people in their struggle for power?"
"Just so."
"In that case", she said, "you must turn it around."
"What do you mean?"
"Ask not which appeals the most to you, but which can do the most for you."
"All right", I said, "I'm asking"
"The Logrus", she said, "will lead you to greatness."
I continued to stare.
"What sort of greatness?" I asked.
"What sort do you desire?"
"I don't know that I ever wanted greatness, on its own.  It seems like wanting to be an engineer, rather than wanting to design something - or wanting to be a writer, rather than wanting to write.  It should be a by-product, not a thing in itself.  Otherwise, it's just an ego trip."

"It's blocking my ability to shift away", Ghost said.
"Give it to me!"
"Why?" I asked.
"That thing has traversed the Logrus"
.."It is theoretically open to all comers", I responded.
"I'm my own law, Merlin, and your Ghostwheel has crossed me before.  I'll have it now."
"No, I do not surrender my creations so readily."

"You would protect him, against me?"
"Yes", she replied.
"I did it for so long that it would be a shame to fail him now, when he really needs it."

"I stand with Merlin", Ghost said, from somewhere.
"Construct!" the Logrus Sign stated.  "You thwarted me in Amber!"
"And a short thwart for the Pattern too", Ghost observed.  "It sort of balances out."
"What is it that you want for yourself, construct?" the Sign inquired.
"To protect one who cares for me."
"I can offer you cosmic greatness!"
"You already did.  I turned you down then too.  Remember?"