The secret of happiness is: Find something more important than you are and dedicate your life to it.

I don't think the 9/11 attacks taught us anything we didn't already know about religion. It has long been obvious - even to the deeply religious - that religious fanaticism is an extremely dangerous deranger of otherwise sane and goodhearted people.

The problem is that no ethical system has ever achieved consensus. Ethical systems are completely unlike mathematics or science. This is a source of concern.

In short, we need to recover the courage we celebrate in our heroes, and in particular, the courage to tolerate, for the sake of a free society, a level of risk we hardly ever imagined in the past.

A child raised on a desert island, alone, without social interaction, without language, and thus lacking empathy, is still a sentient being.

We adore babies because they're so cute. And, of course, we are amused by jokes because they are funny. This is all backwards. It is. And Darwin shows us why.

The juvenile sea squirt wanders through the sea searching for a suitable rock or hunk of coral to cling to and make its home for life. For this task, it has a rudimentary nervous system. When it finds its spot and takes root, it doesn't need its brain anymore so it eats it!

Wherever there is a design that is highly successful in a broad range of similar environments, it is apt to emerge again and again, independently - the phenomenon known in biology as convergent evolution. I call these designs 'good tricks.'