Nick Bostrom

Discovering traces of life on Mars would be of tremendous scientific significance: The first time that any signs of extraterrestrial life had ever been detected. Many people would also find it heartening to learn that we're not entirely alone in this vast, cold cosmos.

Nanotechnology has been moving a little faster than I expected, virtual reality a little slower.

For healthy adult people, the really big thing we can foresee are ways of intervening in the ageing process, either by slowing or reversing it.

Traits acquired during one's lifetime - muscles built up in the gym, for example - cannot be passed on to the next generation. Now with technology, as it happens, we might indeed be able to transfer some of our acquired traits on to our selected offspring by genetic engineering.

Once a discovery has been published, there is no way of un-publishing it.

There are some problems that technology can't solve.

I personally don't think of myself as either an optimist or a pessimist.