Stewart Butterfield

Email is the lowest common denominator. It's the way you get communications from one person to another. There isn't really an alternative. Sometimes people will have Facebook messenger turned on, but 99 percent of the time, if you're sending a message to a human you don't know well, you're using email.

The scale of revenue growth is unprecedented. If you look back over history, whether you're looking at the railway robber baron era or the 1920s or the '50s or the '70s, it used to take a long time for a company to get to the point where they had tens of millions of dollars of revenue. It was almost never an overnight phenomenon.

It is only when you watch the dense mass of thousands of ants, crowded together around the Hill, blackening the ground, that you begin to see the whole beast, and now you observe it thinking, planning, calculating. It is an intelligence, a kind of live computer, with crawling bits for its wits.

Not many people were speaking truth to power in the '80s. I had a really good time doing it - I found it gratifying. It was a joy to have an opportunity to say what you believed. It's challenging to do it in fiction, but I liked writing the novels. I liked writing 'Democracy' particularly.

What's been important with Flickr is the community that's been there from the beginning and the serious photographers that are there creating and sharing great content. If we lose that at some point then I think we have potential issues, but so far we've been able to do a really good job of maintaining that.