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Professor Sagan then offers a comparison that is highly apposite to our present inquiry. 'Today,' he says: we are again seeking messages from an ancient and exotic civilization, this time hidden from us not only in time, but in space. If we should receive a radio message from an extraterrestrial civilization, how could it possibly be understood? Extraterrestrial intelligence will be elegant, complex, internally consistent and utterly alien. Extraterrestrials would, of course, wish to make a message sent to us as comprehensible as possible. But how could they? Is there in any sense an interstellar Rosetta Stone? We believe there is a common language that all technical civilizations, no matter how different, must have. That common language is science and mathematics. The laws of Nature are the same everywhere.3
