Great entrepreneurs focus intensely on an opportunity where others see nothing.

If there is one thing I have learned on this incredible journey we call life, it is this: the sign of a truly successful individual is humility.

Today, people idolize athletes and celebrities - and yes, highly successful and visionary business people like Bill Gates or Steve Jobs, but not the innovators who perhaps have not seen such high-flying levels of success. Can anyone name the inventors of GPS, which has such a huge impact on our lives today?

I have seen humility in many of the finest leaders I have met the world over. And indeed, it is embodied in the warm, engaging and quintessentially successful spirit of Sir Richard Branson.

The real metric of success isn't the size of your bank account. It's the number of lives in whom you might be able to make a positive difference.

Humans have always used our intelligence and creativity to improve our existence. After all, we invented the wheel, discovered how to make fire, invented the printing press and found a vaccine for polio.

All the conservation efforts in the world won't be enough to make a dent in the oncoming sustainability crisis our planet faces.