According to every history of modern science, the past 400 years show we have a great deal to be modest about. Earth is no longer the centre of the universe, the star we orbit is pretty average, and the galaxy we live in is unremarkable. We are here by the same process of evolution as every other plant and animal, and have a lot in common with them. Worst of all, we have only been here for a fraction of the earth's existence, so it is perverse to regard ourselves as the purpose of creation.
It would be fitting for the millennium to end with the final insult - the discovery that even life on earth is not unique. Most attempts to find extra-terrestrials have used radio telescopes to scan the skies for artificial transmissions. But according to Paul Davies (page 18), this assumes that everyone else is like us - no sooner does life arise than it plans to explore space and communicate with other planets.
Finding such life would remove our sense of uniqueness, he says, but it would be less disturbing than finding fossils of primitive, extinct life on Mars. If life can arise and die out there it may do the same here. The finding that Martian life did not develop intelligent status may only emphasise the contingency of our own development with our self-belief, religions and humanist movements.
An obscure consideration perhaps, but one which could accelerate a shift in perception that is already discernible. The main winners are the animal rights and environmental movements: if there is nothing special about us, there is nothing special about our demands on the earth by comparison with those of other creatures. The main loser, organised religion, whose founding texts give man dominion over the earth and all that therein is, and whose more sophisticated protagonists argue for the existence of God from first cause and design - not a random meteor from Mars.