The folks over at Edge annually pick an interesting question and let leading scientists and notables offer short essays to answer. It’s fun and truly thought provoking reading (I hate that phrase, but it’s true here so I’ll use it).

This year the question was What are you optimistic about?, but I found the answers to the 2006 question was “What is your dangerous idea?” even more interesting. My favorite answer to that one comes from Geoffrey Miller:

This is the Great Temptation for any technological species — to shape their subjective reality to provide the cues of survival and reproductive success without the substance. Most bright alien species probably go extinct gradually, allocating more time and resources to their pleasures, and less to their children.

You can read his full answer here (scroll down), as well as the full list of answers by other folks, including Howard Gardner, Jaron Lanier, Daniel Dennett, and Freemon Dyson.