An entrepreneur must deal with more uncertainty than a professional with a well-defined role.

The core problem in our society is political correctness.

There's absolutely no bubble in technology.

Education is a bubble in a classic sense. To call something a bubble, it must be overpriced, and there must be an intense belief in it.

There's always a sense that people will do things quite differently if they think they have privacy.

The optimism that many felt in the 1960s over labour-saving technology is giving way to a fearful question: 'Will your labour be good for anything in the future? Or will you be replaced by a machine?'

I spend an awful lot of time just thinking about what is going on in the world and talking to people about that. It's probably one of my default social activities, just getting dinners with friends.

I think society is both something that's very real and very powerful, but on the whole quite problematic.

You don't want to just do 'me too' companies that are copying what others are doing.

I did not want to write just another business book.

Properly defined, a startup is the largest group of people you can convince of a plan to build a different future.

When I was starting out, I followed along the path that seemed to be marked out for me - from high school to college to law school to professional life.

Whereas a competitive firm must sell at the market price, a monopoly owns its market, so it can set its own prices. Since it has no competition, it produces at the quantity and price combination that maximizes its profits.

I'm very pro-science and pro-technology; I believe that these have been key drivers of progress in the world in the last centuries.

I think it's a problem that we don't have more companies like Facebook. It shouldn't be the only company that's doing this well.

One of my friends started a company in 1997, seven years before Facebook, called SocialNet. And they had all these ideas, and you could be, like, a cat, and I'd be a dog on the Internet, and we'd have this virtual reality, and we would just not be ourselves. That didn't work because reality always works better than any fake version of it.

Investors are always biased to invest in things they themselves understand. So venture capitalists like Uber because they like driving in black town cars. They don't like Airbnb because they like staying in five-star hotels, not sleeping on people's couches.

Every time you write an email, it is in the public domain. There are all these ways where security is not as good as people believe.

Had the people who started Facebook decided to stay at Harvard, they would not have been able to build the company, and by the time they graduated in 2006, that window probably would have come and gone.

How to teach people to do what hasn't been done is a great riddle.

Every correct answer is necessarily a secret: something important and unknown, something hard to do but doable.

Is there something about the gay experience, being gay and the gay experience, that pushes us even more than other people toward competition?

If you're trying to develop a new drug, that costs you a billion dollars to get through the FDA. If you want to start a software company, you can get started with maybe $100,000.

When parents have invested enormous amounts of money in their kids' education, to find their kids coming back to live with them - well, that was not what they bargained for.

What is it about our society where anyone who does not have Asperger's gets talked out of their heterodox ideas?

I would like to live longer, and I would like other people to live longer.

I would not describe myself as a super early adopter of consumer technology.

I believe that evolution is a true account of nature, but I think we should try to escape it or transcend it in our society.

Ideally, I want us to be working on things where if we're not working on them, they won't happen; companies where if we don't fund them they will not receive funding.

The most successful businesses have an idea for the future that's very different from the present - and that's not fully valued.

Credentials are critical if you want to do something professional. If you want to become a doctor or lawyer or teacher or professor, there is a credentialing process. But there are a lot of other things where it's not clear they're that important.

You can achieve difficult things, but you can't achieve the impossible.

In a world where wealth is growing, you can get away with printing money. Doubling the debt over the next 20 years is not a problem.

We live in a world in which courage is in less supply than genius.

Our society, the dominant culture doesn't like science. It doesn't like technology.

As an undergraduate at Stanford, I started 'The Stanford Review,' which ended up being very engaged in the hot debates of the time: campus speech codes, questions about diversity on campus, all sorts of debates like that.

You become a great writer by writing.

In the '30s, the Keynesian stuff worked at least in the sense that you could print money without inflation because there was all this productivity growth happening. That's not going to work today.

In Silicon Valley, I point out that many of the more successful entrepreneurs seem to be suffering from a mild form of Asperger's where it's like you're missing the imitation, socialization gene.

Don't bother starting the 10,000th restaurant in Manhattan. Find something to do that if you don't do it, it won't get done.

There's no single right place to be an entrepreneur, but certainly there's something about Silicon Valley.

I do think there is this danger that our society has made its peace with decline. I'd like to jolt them out of their complacency a little bit.

If I had known how hard it would be to do something new, particularly in the payments industry, I would never have started PayPal. That's why nobody with long experience in banking had done it. You needed to be naive enough to think that new things could be done.

If you borrowed money and went to a college where the education didn't create any value, that is potentially a really big mistake.

We protect monopolies with copyright.

I worked at a law firm in New York very briefly.

'Perfect competition' is considered both the ideal and the default state in Economics 101. So-called perfectly competitive markets achieve equilibrium when producer supply meets consumer demand.

People always say you should live your life as if it were your last day. I think you should live your life as though it will go on for ever; that every day is so good that you don't want it to end.

I believe, basically, that individual freedom is very important.