Grey's Anatomy Season 9 has seen the best and worst of Dr Cristina Yang (Sandra Oh). She fled Seattle, got a "sex friend," and wallowed over her unfortunate past. But Dr Thomas, aka Mr Feeny, taught her to stop skulking. Just like that, Cristina meets world.

At her best, Cristina Yang stands by her friends no matter what. At her worst, she shuns people and uses sex as a distraction. She begins to rediscover herself in the grand scheme of things, thanks to Dr Thomas.

William Daniels, who plays Dr Thomas, is well-loved as man-of-wisdom Mr George Feeny in the '90s American sitcom "Boy Meets World." His motivational lines in both series make a great material for a book. So, move over, "Tuesdays with Morrie." Here's "In the O.R. with Mr Feeny."

Grey's Anatomy: Life Lessons and Quotes from Dr Thomas aka Mr Feeny

"I googled you. I know how to do it, even though I'm old."

"Life is short, you know? You've seen that yourself."

"You know, I was, too. In a plane crash. In Vietnam. Everyone on board the plane died but me."

"Well, you know... it seems like... everything kills you these days."

"Back off, sister." (When Cristina, worried that he would fail, tries to help Thomas.)

"It's been a while since I've had anyone who cared enough to give me grief."

"Watch your language, Dr. Yang. I run a respectable OR."

"Sun's out -- got to take advantage."

"Oh, we're talking about you, now. You should've raised a flag." (After Cristina tells him he couldn't risk being fired because she'd be left alone at the hospital.)

"You love me more than anybody has in a very long time." (An homage to the bond between Mr Feeny and Cory?)

"Look, if I'm going, I wanna go down fighting for something that I believe in."

"Don't be crass. Women of your generation think they have to be crass, or no one will believe their strength."

"Don't hold your breath... When you stop breathing, you stop thinking."

"You will be the surgeon of your generation. I knew it as soon as I met you. People will try to diminish you as they did me, but they will fail."

Finally --

Thomas: Thank God, I never had children. They'd be just like you.
Yang: Come on, I'm your dream come true.
Thomas: That... is the truth.
Yang: You're gonna make me gag.

Click 'Start' to see more quotes from Dr Thomas aka Mr Feeny. Grey's Anatomy fans are compiling memories on Tumblr.

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