Each crisis is different, has its own specificities, and we need to look at it critically; look at each one in its own terms.

Terrorism constitutes a direct attack on the values the UN stands for: the rule of law; the protection of civilians; peaceful resolution of conflicts; and mutual respect between people of different faiths and cultures.

When you have difficult issues on the table for discussion, then sometimes for Africa you may have Burundi or Gambia representing them on the Security Council; and then for Latin America you may have a country like Costa Rica, which is a wonderful country but they don't have the same weight as others from the other regions. And sometimes they get bullied. Sometimes their capitals come under lots of pressure to take a position.

I was an ordinary boy at school, a young man. In fact, what did the headmaster once say? "You're constantly challenging those in authority; questioning and challenging those in authority." Which was not really the way I saw it. I felt there were questions that had to be answered, and things that weren't quite right.

Perhaps the single most successful international agreement to date has been the Montreal Protocol.

Professional accountants should use that influence to encourage the companies they serve to think long term and integrate sustainable development goals into their accounting, such as by including a natural capital account, which I have heard is gaining ground.

To live is to choose. But to choose well, you must know who you are and what you stand for, where you want to go and why you want to get there.