The Search for Terrestrial Intelligence
Once upon a time Extraterrestials monitored planet Earth’s radio output. They sought intelligent life; but they were wary; for their own planet hosted Radar Bats. These were animals naturally evolved, skilled at manipulating electromagnetism, but lacking higher intelligence.
So though planet Earth did indeed emit complex radio signals, the Extraterrestrials were undecided. There were two explanations; Intelligent Beings and Radar Bats. How to tell the difference?
The Extraterrestrials could not predict what a truly intelligent being would transmit. An epic poem in praise of the beauty of the universe, perhaps; or a chapter of the Encyclopedia Galactica; or a proof of the Four-Color Theorem encoded in a symphony. Who knows? But they could easily predict how radar bats would fill the airwaves: with brags, threats, territorial claims, status challenges, mating cries, courtship rites, warning signals and swarming calls.
With this in mind, they decoded planet Earth’s radio output. They found brags, threats, territorial claims, status challenges, mating cries, courtship rites, warning signals and swarming calls; but no cosmic poetry, nor a single page from the Encyclopedia Galactica, nor a single note of the Four-Color Symphony.
They concluded that radio observations have yet to detect intelligent life on planet Earth.
Moral: Intelligence is relative.