"Every man with a new idea is a crank until the idea succeeds."
"The heresy of one age becomes the orthodoxy of the next."
"I am always doing that which I cannot do, in order that I may learn how to do it."
"Most of the change we think we see in life - Is due to truths being in and out of favor."
...Prompted by watching the Dragon's Den (TV1, Monday, 8.30)