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.

Who are we? We find that we live on an insignificant planet of a humdrum star lost in a galaxy tucked away in some forgotten corner of a universe in which there are far more galaxies than people.

If we are merely matter intricately assembled, is this really demeaning? If there's nothing here but atoms, does that make us less or does that make matter more?

When permitted to listen to alternative opinions and engage in substantive debate, people have been known to change their minds. It can happen.

There is a reward structure in science that is very interesting: Our highest honors go to those who disprove the findings of the most revered among us. So Einstein is revered not just because he made so many fundamental contributions to science, but because he found an imperfection in the fundamental contribution of Isaac Newton.

In the fabric of space and in the nature of matter, as in a great work of art, there is, written small, the artist's signature.

Perhaps the depth of love can be calibrated by the number of different selves that are actively involved in a given relationship.