Many great startup ideas fall into the 'sounds like a bad idea, is a good idea' category. In fact, most of them do. These are the most dangerous ideas—the ones that sound plausibly good but aren't. There was nobody desperate for a social network for sports fans, so it failed.

We end up living in the world virtually through the ideas that we conceive.

I don't really like the term entrepreneur because I think to some it implies that you start businesses for the sake of starting businesses. My view is this. If there's something you want to see in the world that doesn't exist, go build that thing. If that means you have to build a company? so be it.

I was the kid that was wondering what was faster, a car or a bee… what if garbage cans were gold… I'd posit these what-if questions and throw them to people around me.

I remember being on a spacewalk and had a few seconds to see a view that humans were not meant to see. It was like I was hearing from God. But then, I had to get back to work.

A lot of people assume that I would choose not to have bipolar disorder; but I'm grateful for it. I wouldn't trade it for anything in the world, because I feel like all the ups and downs have formed who I am, and made be braver, tougher… more creative and more capable.

I didn't have a childhood- I didn't play- every day was about survival. I was always moving to a different-place on a weekly/monthly basis.

There is no such thing as true-altruism (even philanthropists get something out of giving!). What is this individuals' payoff from working with you?

I flew home with this profound sense of the simultaneity of human suffering; I've never been able to get over that sense that even as I'm talking to you right now, there are people who are living unbearable lives.

We don't always see change and activism from the perspective of what we're giving, it's too often about taking things away… Don't eat that… don't do that… don't drive that car… we have to reframe and rethink. Imagine if we told people we could give them the universe back, it's a beautiful gift- but also allows us to save energy, birds, insects and more.

You are surrounded by an endless series of expanded layers of social networks. Your inner core is 5, which extends to 50-150, 500 and eventually out to around 1500. As you go out through the networks, the number of people included increases, the average quality of these relationships declines.

Your competitors are looking for the product, idea or feature that gives such a competitive advantage that they can take all your customers away from you. You need to work like someone's trying to take it all away from you, because they are.