What advice would you give your twenty-year-old self, and what should they ignore?

Luckily, I got at a very early age the idea that the safest way to try and get what you want is to try and deserve what you want. It's such a simple idea. It's the golden rule so to speak. You want to deliver to the world what you would buy if you were on the other end. There is no ethos, in my opinion, that is better for any lawyer or any other person to have.

One day, I spoke to him about my sense of shame. He looked me in the eyes and told me that brewing was a science; it was not about getting drunk. He did not stop there. He said: 'Do not make judgment on things, people, and issues with half information.' He said there is truth in everything you see around. So, look for everything in its entirety. That was a game-changing moment for me.

I would hope that most of you will in fact strive for leadership in a principled manner with values, because that would be the foundation that this country needs to have if it is to take its place in the world. I would hope that each of you would lead by example and that each of you would live by the principles that you espouse.

Never give up your passion for learning. And zoom out of your field before you zoom in. Some of my very best business insights have come from reading around subjects. They have come from approaching questions at a strange angle, from thinking about them from a different point of view. A lot of the knowledge that has really given me an edge in business has come from history, psychology, even chemistry. Connecting seemingly unconnected dots is what has served me well.

Don't screw it up. Don't take it for granted. Try new things, even if you're old. Do the right thing, because if you do the right thing, the money will follow. Decide what you stand for. Finally, don't worry about being cool—be warm.