The development of sophisticated ethical systems seems fairly necessary for a society to reach high technological sophistication; a species gets intelligent only through intense competition, and it survives its advance through fission and fusion only when it can learn to add cooperation and tolerance to competition, the balance of the three forming the base of the advanced ethical system.
Eggs Ackley. So, when Fermi asked, Where are they, not everyone raised their hands (antenni) at once. These beings may well walk among us, as some have pointed out, Democrats. When confronted, they won't admit they're from outer space. Just try to get a cat to admit to being from outer space. They never will. But you know they are. And what about that shop teacher in Junior High. You know he was. Betty Crocker and Uncle Ben, both of them were. Nobody knows where these people came from, or where they went. Harley Earl, he's designing Wentlers on Saturn. Dick Nixon, he's got a low level cabinet post on Jupiter. Take a close look at Leon Panetta. They're out there.