Someone told me that each equation I included in the book [*A Brief History of Time *] would halve its sales.

God not only plays dice. He also sometimes throws the dice where they cannot be seen.

Even if there is only one possible unified theory, it is just a set of rules and equations. What is it that breathes fire into the equations and makes a universe for them to describe? The usual approach of science of constructing a mathematical model cannot answer the questions of why there should be a universe for the model to describe. Why does the universe go to all the bother of existing?

Disorder increases with time because we measure time in the direction in which disorder increases.

A theory is a good theory if it satisfies two requirements: it must accurately describe a large class of observations on the basis of a model that contains only a few arbitrary elements, and it must make definite predictions about the results of future observations.

Thirty years ago I was diagnosed with motor neurone disease, and given two and a half years to live. I have always wondered how they could be so precise about the half.

Why does the universe go to all the bother of existing?

My goal is simple. It is complete understanding of the universe, why it as it is and why it exists as all.

I'm not afraid of death, but I'm in no hurry to die. I have so much I want to do first.

There is no heaven or afterlife for broken-down computers; that is a fairy story for people afraid of the dark.