The illegality of cannabis is outrageous.

A millennium before Europeans were willing to divest themselves of the Biblical idea that the world was a few thousand years old, the Mayans were thinking of millions and the Hindus billions.

It's hard to kill a creature once it lets you see its consciousness.

After the earth dies, some 5 billion years from now, after it's burned to a crisp, or even swallowed by the Sun, there will be other worlds and stars and galaxies coming into being - and they will know nothing of a place once called Earth.

Virtually every major technological advance in the history of the human species - back to the invention of stone tools and the domestication of fire - has been ethically ambiguous.

Our loyalties are to the species and the planet. We speak for Earth. Our obligation to survive is owed not just to ourselves but also to that Cosmos, ancient and vast, from which we spring.

Extraordinary claims demand extraordinary evidence