If you, like me, routinely scan the non-fiction book review pages, you may, like me, have noticed a genre particularly popular at the moment: futurology. We live with a fin de siècle feeling. What's striking, though, is that the genre is divided down the middle. On one side are writers who see a bright future stretching out before us. There will be problems. But technologies of various sorts are ready to hand - the internet, space travel, medical breakthroughs. Heaven will be a place on earth, or at least somewhere in the cosmos.

On the other side are writers who see little but darkness facing us. Perennial problems will return to haunt us and there's at least an even chance they will destroy us - resource wars, climate change, mass epidemic. Technologies may ease the pain for some, but technology can't tackle the root problem, which is we ourselves. After all, centuries of technological advance, even when coupled to enlightenment thinking, have done little or nothing to reduce the scale of wars, the presence of poverty, the blight of corruption and crime. Our future is more like Blade Runner than Star Trek.

Whose side are you on? It seems to me that will depend upon what you make of what it is to be human. If you tend to feel that the powers of humankind can reach to infinity, to invoke the words of one optimistic title being reviewed at the moment, then you'll incline to the view that human beings will, in time, adopt most of the capacities that once belonged to the gods - near omniscience, omnipotence and omnipresence in the cosmos.

But if you feel that human beings tend to find themselves dwelling in the gutter whilst gazing at the stars, to recall Oscar Wilde's sense of things, then fooling yourself that we are on the way to divinity is a form of self-delusion, even blasphemy. Rather, we are situated between the beasts and the angels. The future will remain forever uncertain, which is to say it will catch us unawares. Our geniuses will inspire us and give us iPads, but our flaws will not let us go.