We have to get rid of those nuclear weapons.

Civilization will end within 15 or 30 years unless immediate action is taken against problems facing mankind.

There's life all over this universe, but the only life in the solar system is on earth, and in the whole universe we are the only men.

A lecture is much more of a dialogue than many of you probably realize.

When it comes to the origin of life there are only two possibilities: creation or spontaneous generation. There is no third way. Spontaneous generation was disproved one hundred years ago, but that leads us to only one other conclusion, that of supernatural creation. We cannot accept that on philosophical grounds; therefore, we choose to believe the impossible: that life arose spontaneously by chance!

We have fallen in love with the body. That's that thing that looks back at us from the mirror. That's the repository of that lovely identity that you keep chasing all your life.

I think if a physician wrote on a death certificate that old age was the cause of death, he'd be thrown out of the union. There is always some final event, some failure of an organ, some last attack of pneumonia, that finishes off a life. No one dies of old age.