To me we are faced with two choices, that life exists on earth as a unique event. The conditions arising from the sheer enormity of space and the probability of convergent factors. The other that life is commonplace, a infinite number of life harbouring planets exist in the universe. I think it's the former, we sit alone. All that's out there are worlds much akin to mars, lifeless crater scarred and inhospitable. But we hanker for the romance of 'little green men' because the opposite is too hard to bear. The countless hours we spend probing space, the pioneering spirit that keeps our eyes glued to the sky- all wasted.