Discussing the possibilities of extraterrestrial life: I would love it even if they were short, sullen, grumpy and sexually obsessed. But there just isn't any good evidence.
What began in deadly competition has helped us to see that global cooperation is the essential precondition for our survival. Travel is broadening. It's time to hit the road again.
The prediction of nuclear winter is drawn not, of course, from any direct experience with the consequences of global nuclear war, but rather from an investigation of the governing physics.
The vast distances that separate the stars are providential. Beings and worlds are quarantined from one another. The quarantine is lifted only for those with sufficient self-knowledge and judgment to have safely traveled from star to star.
In many cultures it is customary to answer that God created the universe out of nothing. But this is mere temporizing. If we wish courageously to pursue the question, we must, of course ask next where God comes from? And if we decide this to be unanswerable, why not save a step and conclude that the universe has always existed?
The immense distances to the stars and the galaxies mean that we see everything ins pace int he past, some as they were before the Earth came to be. Telescopes are time machines.
Science is a way to call the bluff of those who only pretend to knowledge. It is a bulwark against mysticism, against superstition, against religion misapplied to where it has no business being.
If we offer too much silent assent about mysticism and superstition - even when it seems to be doing a little good - we abet a general climate in which scepticism is considered impolite, science tiresome, and rigorous thinking somehow stuffy and inappropriate.
An extraterrestrial being, newly arrived on Earth - scrutinizing what we mainly present to our children in television, radio, movies, newspapers, magazines, the comics, and many books - might easily conclude that we are intent on teaching them murder, rape, cruelty, superstition, credulity, and consumerism. We keep at it, and through constant repetition many of them finally get it.
It will not be we who reach Alpha Centauri, and the other nearby stars. It will be a species very like us - but with more of our strengths and fewer of our weaknesses.
One of the reasons for its success is that science has a built-in, error-correcting machinery at its very heart. Some may consider this an overbroad characterization, but to me every time we exercise self-criticism, every time we test our ideas against the outside world, we are doing science. When we are self-indulgent and uncritical, when we confuse hopes and facts, we slide into pseudoscience and superstition.
Eratosthenes was the director of the great library of Alexandria, the Centre of science and learning in the ancient world. Aristotle had argued that humanity was divided into Greeks and everybody else, whom he called barbarians and that the Greeks should keep themselves racially pure. He thought it was fitting for the Greeks to enslave other peoples. But Erathosthenes criticized Aristotle for his blind chauvinism, he believed there was good and bad in every nation.