There is nothing outside the universe.

But in spite of the obvious effectiveness of mathematics in physics, I have never heard of a good a prioriargument that the world must be organised to mathematical principles.

The page of my notebook was filled with many messy integrals, but all of a sudden I saw emerge a formula for counting. I had begun to calculate a quantity on the assumption that the result was a real number, but found instead that, in certain units, all the possible answers would be integers. This meant that areas and volumes cannot take any value, but come in multiples of fixed units.

Those who do good science do so because they choose problems that are suited to them.

Surprise is inherent in the structure of the world.

There is nothing outside the universe.

We know no more than we did in 1975 - and that's not good