What is the most important lesson life has taught you?

It is necessary, I believe, to accept this idea, not only for science, but also for other things; it is of great value to acknowledge ignorance.  It is a fact that when we make decisions in our life we don't necessarily know that we are making them correctly; we only think that we are doing the best we can – and that is what we should do.

I'm convinced that about half of what separates the successful entrepreneurs from the non-successful ones is pure perseverance. It is so hard. You put so much of your life into this thing. There are such rough moments in time that I think most people give up. I don't blame them. Its really tough and it consumes your life.

It's family, and it's faith, and it's friends. I would tell them that. Don't forget that. In your brilliance, don't turn your back on your friends. Don't think you're entitled to something because you're smarter than the next guy.

So achievement, to me, is something that just comes with this attitude of doing your work the best you can in a passionate way. It’s not something that you have to expect. It’s something that’s a consequence of what you do, but it’s certainly important.

I might have made a tactical error in not going to a physician for 20 years. ... It's one of those phobias that didn't pay off. ... How much you're supposed to enjoy every sandwich.

Not really. I thought that getting the Nobel Prize was a big interruption in my career, I thought and it was very distracting. It takes a lot of time you know, it just takes time to be honoured, you have to travel and you have to give speeches of things you have, oh it’s so often that you get bored to tears when you hear your own voice. And it’s really taking a lot of your time and there’s no way that during this time you can start something new, I mean you just profit from what you’ve done and there is no time to develop new ideas.

I think that is the most important lesson you learn in life, that you have to be ready to make a compromise. You do not compromise your principles, but you have to be ready to compromise. You have to understand that you cannot get your way 100 percent. Life is too complicated. You are not an island, and you work in a social setting, and you need to understand that you work always — at the family level, at the society level — to work out the compromise that is perceived to be fair. You don’t get 100 percent of what you want, but at least you will get the basic minimum that you require.

Every mischance in life was an opportunity to learn something and your duty was not to be submerged in self-pity, but to utilize the terrible blow in a constructive fashion.

Don't let MGM distribute a film you care about.

It occurred to me that at one point it was like I had two diseases – one was Alzheimer's and the other was knowing I had Alzheimer's. There were times when I thought I'd have been much happier not knowing, just accepting that I'd lost brain cells and one day they'd probably grow back or whatever. It is better to know, though, and better for it to be known, because it has got people talking, which I rather think was what I had in mind.

So I think failure is important in my career.

To stand up tall and aim for what you want.

To be humble is to be sane.

A 'no' is free.

To fail better next time.

I think the only life experience that I have to offer out of this is something we all know in the abstract but don't experience in practice very much. That is that you can survive an awful lot of bad stuff, so long as your mind is intact. I'm afraid that's the only life experience I have to offer.

My mentor heard it and said, “Derek, you’re just not a singer. You really need to stop trying. Admit you’re a songwriter, and find a real singer.”

I believe that if, at the end, according to our abilities, we have done something to make others a little happier, and something to make ourselves a little happier, that is about the best we can do. To make others less happy is a crime. To make ourselves unhappy is where all crime starts. We must try to contribute joy to the world. That is true no matter what our problems, our health, our circumstances. We must try. I didn’t always know this and am happy I lived long enough to find it out.

Yes. I'm not unhappy about becoming old. I'm not unhappy about what must be. It makes me cry only when I see my friends go before me and life is emptied. I don't believe in an afterlife, but I still fully expect to see my brother again. ... But, you know, there's something I'm finding out as I'm aging that I am in love with the world. And I look right now, as we speak together, out my window in my studio and I see my trees and my beautiful, beautiful maples that are hundreds of years old, they're beautiful. And you see I can see how beautiful they are. I can take time to see how beautiful they are. It is a blessing to get old. It is a blessing to find the time to do the things, to read the books, to listen to the music.

Before I was diagnosed with esophageal cancer a year and a half ago, I rather jauntily told the readers of my memoirs that when faced with extinction I wanted to be fully conscious and awake, in order to “do” death in the active and not the passive sense. And I do, still, try to nurture that little flame of curiosity and defiance: willing to play out the string to the end and wishing to be spared nothing that properly belongs to a life span. However, one thing that grave illness does is to make you examine familiar principles and seemingly reliable sayings. And there’s one that I find I am not saying with quite the same conviction as I once used to: In particular, I have slightly stopped issuing the announcement that “Whatever doesn’t kill me makes me stronger.”