challenge Quotes

My first popular book, 'A Brief History of Time,' aroused a great deal of interest, but many found it difficult to understand.

It's hard to improve public education - that's clear.

In low-income countries, getting to a health post is hard. It's very expensive.

By the time we see that climate change is really bad, your ability to fix it is extremely limited... The carbon gets up there, but the heating effect is delayed. And then the effect of that heat on the species and ecosystem is delayed. That means that even when you turn virtuous, things are actually going to get worse for quite a while.

Security is, I would say, our top priority because for all the exciting things you will be able to do with computers - organizing your lives, staying in touch with people, being creative - if we don't solve these security problems, then people will hold back.

The typical project design time for a large company like IBM - and they keep track of this - is a little over four years.

Philanthropy should be taking much bigger risks that business. If these are easy problems, business and government can come in and solve them.

In order for the United States to do the right things for the long term, it appears to be helpful for us to have the prospect of humiliation. Sputnik helped us fund good science - really good science: the semiconductor came out of it.

Whether it's Google or Apple or free software, we've got some fantastic competitors and it keeps us on our toes.

The year I was born, 1955, the first big disease-eradication program in the world was declared for malaria. After about a decade of work, they realized that, at least in the tropical areas, they did not have the tools to get it done.