It's humbling to realise that the developmental gulf between a miniscule ant colony and our modern human civilisation is only a tiny fraction of the distance between a Type 0 and a Type III civilisation - a factor of 100 billion billion, in fact. Yet we have such a highly regarded view of ourselves, we believe a Type III civilisation would find us irresistible and would rush to make contact with us. The truth is, however, they may be as interested in communicating with humans as we are keen to communicate with ants.

Our grandkids will lead the lives of the gods of mythology. Zeus could think and move objects around. We'll have that power. Venus had a perfect, timeless body. We'll have that, too. Pegasus was a flying horse. We'll be able to modify life in the future.

There are many examples of old, incorrect theories that stubbornly persisted, sustained only by the prestige of foolish but well-connected scientists... Many of these theories have been killed off only when some decisive experiment exposed their incorrectness... Thus the yeoman work in any science, and especially physics, is done by the experimentalist, who must keep the theoreticians honest.

Our best shot at finding life in our solar system might be to look at the moons of Jupiter and Saturn. Mars, increasingly, looks like a dead planet. But the oceans beneath the ice cover of the moons of Jupiter and Saturn may actually have more liquid water than the oceans of Earth.

Global warming is controversial, of course, but the controversy is mainly over whether human activity is driving it.

"Did God have a mother?" Children, when told that God made the heavens and the earth, innocently ask whether God had a mother. This deceptively simple question has stumped the elders of the church and embarrassed the finest theologians, precipitating some of the thorniest theological debates over the centuries. All the great religions have elaborate mythologies surrounding the divine act of Creation, but none of them adequately confronts the logical paradoxes inherent in the question that even children ask.

So often, science fiction helps to get young people interested in science. That's why I don't mind talking about science fiction. It has a real role to play: to seize the imagination.