Exhibition: Alien Revolution, Greenwich
"No-one would have believed," writes HG Wells in his famous opening for The War Of The Worlds, "in the last years of the 19th century that this world was being watched keenly and closely by intelligences greater than man's."
No-one would have believed! Wells clearly wasn't browsing the internet.
Someone somewhere is believing most things and the existence of life beyond our planet appears to be the receptacle of choice in which to decant the latest extreme thinking, providing a warm embrace for a spectrum of theories from the sinister to the scientific.
This new exhibition - with accompanying planetarium shows and talks - explores the history of ideas surrounding our search for extra-terrestrials.
What becomes apparent is that imposed upon ET are the beliefs, fears and hopes of the time he is sought, from the fantastical realms of life before the enlightenment, through the wrestling and wrangling with the anthropic principle on to the paranoia of the Cold War.
Although we are taking the whole business more seriously these days, the fact we are in thrall to Mars Curiosity's distant digging shows that romanticism is still rampant.
Carl Sagan said: "I am often asked, 'Do you believe in UFOs?' I'm always struck by how the question is phrased, the suggestion that this is a matter of belief and not evidence. I'm almost never asked, 'How good is the evidence that UFOs are alien spaceships?'"
Although right about extra-terrestrials, Sagan misses the point about the humans posing the question.
In response to the Big Question about whether there is or isn't either answer is so mind-blowing that religiosity has the best vocabulary.
Until Sept 8, go to rmg.co.uk.
Image: Lunar Life by Leopoldo Galluzo, 1836 © Smithsonian