It is a long video, but it is well worth watching.
Quotes from the lecture:

"Brick walls are there for a reason. The brick walls are not there to keep us out. The brick walls are there to show how badly we want something."
"Find the best in everybody…. Wait long enough, and people will surprise and impress you."
"Decide if you’re a Tigger or an Eyeore. I’m a Tigger."

Powerful Video