The health of your family or your office or your city directly affects the health of it after. The better you are at handling high-stress situations with little information, those skills lead to resilience and the ability to recover afterward.

People with military experience seem to do very well in these situations. They've been taught that they can control their destiny, which is half the battle. They also have some experience in getting out of bad situations even if just through training. They know they have to make a plan and follow it and execute it.

By sort of combining the research of a lot of smart people, I came up with an equation for dread [dread=uncontrollability+unfamiliarity+imaginability+suffering+scale of destruction+unfairness]. The dread equation is a simplification, but it's a way to explain why we fear something so much when it is so unlikely. Part of it is the lack of control. That's why we're more scared of plane crashes than car crashes even though we know rationally which is more dangerous.

The one thread that was most surprising and most consistent was the lack of fear that people felt at the worst moment. They felt a lot of fear in early stages, when they're just realizing what's happening. But then things really seemed to be at their peak of terror, the fear went away. You can imagine why that's useful. At that moment your brain needs to focus all its attention on surviving, so people will feel a sense of calm as their brain tries to sort out a plan.

Most serious plane crashes are survivable. There's a sense that, 'Oh, if we go down, that's it, it's out of my hands.' And that's just statistically not true. I have more optimism and more faith that my own actions can make a difference.

You could reduce people's fears if you gave them some useful information before things went wrong. It's really important to create a sense of confidence in the public in their own abilities before a disaster because they're the only ones who are going to be there. No one's going to help you for at least 24 to 72 hours. So it would be good to know more about it.

People will help each other because there is a sense of camaraderie that springs up, which is a survival tactic. You help them because you know you might need their help later. And that is incredibly reassuring.