If we want to have the biggest impact, the best way to do this is to make sure we always focus on solving the most important problems.

Just because you can build a machine that is better than a person at something doesn't mean that it is going to have the ability to learn new domains or connect different types of information or context to do superhuman things. This is critically important to appreciate.

Think about what people are doing on Facebook today. They're keeping up with their friends and family, but they're also building an image and identity for themselves, which in a sense is their brand. They're connecting with the audience that they want to connect to. It's almost a disadvantage if you're not on it now.

In a recent survive of Millennials around the world asking what most defines our identity, the most popular wasn't nationality, ethnicity or religion. It was "citizen of the world." That's a big deal. Every generation expands the circle of people we consider one of us. And in our generation, that now includes the whole world. This is the struggle of our time. The forces of freedom, openness, and global community against the forces of authoritarianism, isolationism, and nationalism - forces for the flow of knowledge, trade, and immigration, against those who would slow them down.

What Facebook stands for in the world is giving people a voice and spreading ideas and rationalism.

When I look around the world and see so many countries turning people away, I think it is terrible. And I know that these are all issues that Germany is culturally dealing with in terms of integration but it is just something that I deeply admire.

I generally think if you do good things for people in the world, that comes back and you benefit from it over time.