What if we aren’t alone after all?
Throughout history there have been visionaries, dreamers – or madmen, according to one’s point of view. In the Book of Revelation, Saint John claimed to have seen ‘a new heaven and a new earth’. Chaucer, in the Dream Vision The House of Fame, travels into the heavens on the back of an eagle, which tells him that ‘in this region, certeyn, dwelleth many a citezeyn’. Giordano Bruno in the sixteenth century argued for an infinite number of inhabited worlds, with intelligent beings existing on other planets throughout the universe.
And until two hundred years ago, the visionaries and the dreamers had reason on their side. The belief that the universe was only a few thousand years old was so commonplace that Shakespeare’s Rosalind could mention it in passing: ‘The poor world is almost 6,000 years old.’ In such a young universe only intelligent design could be a satisfactory explanation for complexity and diversity, and a God-created universe could contain all kinds of wonders. It is no surprise that William Blake saw angels in the trees of Peckham Rye, and that Emanuel Swedenborg claimed he had conversed with spirits from Mars, Venus, Mercury, Saturn, Jupiter and the moon.
But within these last two centuries our understanding of the universe has been transformed, as has our knowledge of life on Earth. Geology gave us the timescale necessary for evolution to take place; Darwin and Wallace proposed the mechanism, for which DNA and genetics provide the tools. On Earth we have discovered that we are not alone; instead of being a unique species, we now realise that homo sapiens is but one member of a large family of hominids. It is only the recent extinction of the last of these, the Neanderthals, that has given us the illusion of being unique.
The change has been from speculation to investigation, from vision to observation. Every decade has furthered our knowledge and understanding, to the point we have at last reached: we are on the threshold of discovering planets that could harbour life like ours, life that we could recognise and investigate on a scientific basis. The pace of discovery is rapid and accelerating, because we recognise the significance of the search and are devoting enormous resources to it. Twenty years ago we had no positive evidence of the existence of extrasolar planets. Now we know of 700, and the Kepler mission indicates that there may be 50 billion in our galaxy alone. Already the astrophysicist Steven Vogt has claimed that the likelihood of life existing on the unromantically named planet Gliese 581g is ‘100%’.
What would be the consequences of such a discovery, even if it were of the merest microbial life form on a planet orbiting a distant star? Our species has developed its beliefs, its cultures, its religions on the basis of our uniqueness, on the theory that the universe was designed expressly, perhaps solely, for us. Incontrovertible proof that we are not alone would force us to re-examine all our knowledge, to build new theories of life, its origins, its diversity, perhaps its purpose. If we discover one life form we will discover many, for the universe is huge and the number of stars almost uncountable. Somewhere out there, almost certainly, would be life forms that possess intelligence recognisably like our own, for they will have developed by the same laws of evolution, bound by the same physics and chemistry that we know on Earth.
It is an exciting time to be alive. We stand maybe on the very verge of revelation, one that is less mystical than Saint John’s, but one which we can all understand and share, and which would affect the hearts and minds of every one of us.
Throughout October and November, The Independent Online is partnering with the Institute of Ideas’ Battle of Ideas festival to present a series of guest blogs from festival speakers on the key questions of our time.
Richard Swan is a writer, teacher, and former vice-principal of Harvey Grammar School, Folkestone. He is producing the Battle of Ideas session Life Off Earth: are there aliens out there? which takes place on Sunday 30 October.Tagged in: alien, opinion, space, universe
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