"One day, I shall come back. Yes, I shall come back. Until then, there must be no regrets, no tears, no anxieties. Just go forward in all your beliefs and prove to me that I am not mistaken in mine." - First Doctor, Doctor Who

"There are some corners of the universe which have bred the most terrible things. Things which act against everything we believe in. They must be fought." - Second Doctor, Doctor Who

"A straight line may be the shortest distance between two points, but it is by no means the most interesting." - Third Doctor, Doctor Who

"You know, the very powerful and the very stupid have one thing in common. They don't alter their views to fit the facts. They alter the facts to fit the views. Which can be uncomfortable if you happen to be one of the facts that needs altering." - Fourth Doctor, Doctor Who

"Dreams are important, Nyssa. Never underestimate them. Once a man fell asleep and dreamt he was a frog. When he woke up, he didn't know if he was a man who dreamt he was a frog or a frog who was now dreaming he was a man." - Fifth Doctor, Doctor Who

"In all my travelling throughout the universe, I have battled against evil, against power-mad conspirators. I should have stayed here. The oldest civilisation: decadent, degenerate, and rotten to the core. Power-mad conspirators, Daleks, Sontarans, Cybermen - they're still in the nursery compared to us. Ten million years of absolute power. That's what it takes to be really corrupt." - Sixth Doctor, Doctor Who

"There are worlds out there where the sky is burning, and the sea's asleep, and the rivers dream; people made of smoke and cities made of song. Somewhere there's danger, somewhere there's injustice, and somewhere else the tea's getting cold. Come on, Ace. We've got work to do." - Seventh Doctor, Doctor Who

"No, not at all. I’ve been too methodical recently, I think. Setting coordinates and things, actually deciding where we want to go. I’ve been getting far too safe and predictable these last few incarnations. Do you know I once traveled for centuries without ever knowing where I’d materialize next?" - Eighth Doctor, Doctor Who