Fundamental sense of well-being crucially depends on our having the ability to exert control over our environment and recognising that we do.

The past 10 days have been 'the most dramatic in Wall Street's 216-year history' seeing Lehman Brothers collapse, AIG fall into critical distress, and the US Federal Reserve creating a c. US$1 Trillion rescue plan to 'save the world'.

After working with esteemed leaders across six continents, I've observed that the singular trait they all share is their imperfection. Recognizing and embracing one's imperfections, while acknowledging that you don't have all the answers, is the foundation of great leadership.

Our past technologies, such as hammers, didn't manipulate or influence our weaknesses… they didn't have a business model dependent on building a voodoo doll of the hammer owner that allowed them to predict the hammer owner's behaviour, showing them videos of home construction such that mean they use the hammer every day. A hammer is just sitting there patiently waiting to be used.

Here I am the fool looking to fail frequently. I want to either hit a homerun or walk or even strike out. This means I fail far more often than I succeed. But the important point is that what I lose when I fail is trivial, epsilon compared to what I make when I succeed.

As humans, we've evolved in a world where the pace of change was slow. Our minds are not structured for the pace of rapid change that we're seeing and, increasingly, will experience. One way that we deal with the accelerating rate of change is by sort of riding on top of that tsunami of change rather than being crushed by it.

The truth is nobody needs a diamond. You don't need a diamond to heat your home, run your car or power your cell-phone. As a business, it's clear to us that there is only one source of value for diamonds- and that is the consumer's desire for the product. 99% of diamond demand is from the jewellery industry, less than 1% goes to industrial uses.

If you look at the notional value of trading on our exchanges in any given year, they range from $600-700 trillion to a quadrillion (1000 trillion) dollars in total value. People can use these markets very effectively, not just for bona-fide risk hedging and transfer and risk management but also for asset allocation, portfolio management and trading strategies as well.

Critical narratives are centered on the idea of moral complicity in these evils and use very sophisticated rhetorical ways to get people to feel that guilt and to believe in their complicity. They use very obscure language that involves a lot of double-meaning and multiple-meaning to words so that people it confronts feel stupid.

The way you eliminate fear is to approach your situation from every angle, almost as though it were a logic puzzle. It's also setting a goal but not being afraid to back away if you think that you're going to do irreversible damage on the way there.

As I said earlier, the only source of value in our business is the consumer's desire for the product. That desire is built on emotions ascribed to diamonds, and if they believe the way that diamond has been brought to their finger does anything other than live up to the values they ascribe to it, we would have a major problem.

Too often when we find someone disagreeing with us, our question is about why. Why do you believe this ridiculous thing? What tends to work better is a how question... This kind of approach helps to view the real complexity of a situation and reveals gaps in knowledge.