"His ignorance was as remarkable as his knowledge."

"Our ideas must be as broad as Nature if they are to interpret Nature."

"How often have I said to you that when you have eliminated the impossible, whatever remains, however improbable, must be the truth?"

"Depend upon it there comes a time when for every addition of knowledge you forget something that you knew before. It is of the highest importance, therefore, not to have useless facts elbowing out the useful ones."

"The 50-50-90 rule: Anytime you have a 50-50 chance of getting something right, there's a 90% probability you'll get it wrong."

"When families are strong and stable, so are children - showing higher levels of wellbeing and more positive outcomes. But when things go wrong - either through family breakdown or a damaged parental relationship - the impact on a child's later life can be devastating."

"True knowledge is found not in possessing answers, but in continually asking the right questions. Remember this in moments of decisive trial."

"Well, you know, a lot of people look at the negative things, the things that they did wrong and - which I do. But I like to stress on the things I did right, because there are certain things that I like to look at from a positive standpoint that are just positive reinforcement."