You simply can't be tentative in a startup. You have to go for it at every chance you get. And if the leader of the organization is anxious, his or her fear pervades the organization. Everything comes from the top in a company. So if you are starting a company or building one, face your fears and move past them. It's critically important to your company.

Ideas that most people derided as ridiculous have produced the best outcomes. Don't do the obvious thing.

My venture investing career has three phases, all roughly 6-8 years long. The first, at Euclid, was software to Internet. The second, at Flatiron, was Internet to bubble. And the third, at USV, has been web 2 to mobile. I have always used a new firm to denote a new investment phase for me. Throw away the old. Start with the new.

If you have a native monetization system where the atomic unit of content is the ad unit, that scales down all the way to a small screen experience. That's why Twitter is performing so well on mobile.

Foursquare's adoption of a game dynamic when it launched is a particularly clever implementation of a social hook.

I generally blog between 5:30 A.M. and 7 A.M. I will from time to time add something during the day, but for the most part blogging is an early morning activity for me.

We need new medical approaches to preventing and/or curing disease. We need new scientific approaches to generating, storing, and being more efficient with energy. Maybe we need more space exploration. Maybe we need more undersea exploration.