There is a maxim about the universe which I always tell my students: That which is not explicitly forbidden is guaranteed to occur.

What people believe impacts on what they do. And it's not as if religion is universally bad. Of course it's responsible for many peoples doing good actions.

The root cause of the looming energy problem - and the key to easing environmental, economic and religious tensions while improving public health - is to address the unending, and unequal, growth of the human population. And the one proven way to reduce fertility rates is to empower young women by educating them.

We all trust each other to some extent. We have to rely on experts to some extent, but we should learn to be sceptical.

It really is the most poetic thing I know about physics: you are all stardust.

Neutrinos alone, among all the known particles, have ethereal properties that are striking and romantic enough both to have inspired a poem by John Updike and to have sent teams of scientists deep underground for 50 years to build huge science-fiction-like contraptions to unravel their mysteries.

The fact is that people would rather cling when they're afraid of something to a priori beliefs than rather open their minds about it.