What an odd, ruminating, noisy, self-interrupting conversation we conduct with ourselves from birth to death.

Which is crueler, an old man's lost memories of a life lived, or a young man's lost memories of the life he meant to live?

Artificial intelligence is growing up fast, as are robots whose facial expressions can elicit empathy and make your mirror neurons quiver.

Our sense of safety depends on predictability, so anything living outside the usual rules we suspect to be an outlaw, a ghoul.

Not much is known about alligators. They don't train well. And they're unwieldy and rowdy to work with in laboratories.

As people flock to urban centers where ground space is limited, cities with green walls and roofs and skyscraper farms offer improved health and well-being, renewable resources, reliable food supply, and relief to the environment.

The further we distance ourselves from the spell of the present, explored by our senses, the harder it will be to understand and protect nature's precarious balance, let alone the balance of our own human nature.