I personally don't invest in a lot of companies because I think it would be a conflict of interest and Facebook doesn't typically either.

The question I ask myself like almost every day is: ‘Am I doing the most important thing I could be doing?' Unless I feel like I’m working on the most important problem that I can help with, then I’m not going to feel good about how I’m spending my time. And that’s what this company is.

Move fast and break things. Unless you are breaking stuff, you are not moving fast enough.

The only meat I eat is from animals I've killed myself.

We should have a society that measures progress not just by economic metrics like GDP, but by how many of us have a role we find the meaningful. We should explore ideas like universal basic income to make sure everyone has a cushion to try new ideas.

Find that thing you are super passionate about. A lot of founding principles of Facebook are that if people have access to more information and are more connected, it will make the world better; people will have more understanding, more empathy. That’s the guiding principle for me. On hard days, I really just step back, and that’s the thing that keeps me going.

In my experience everyone will have a different view of the right level of tax so governments need to provide clear guidance that conforms to a set of international standards that all governments accept.