Well, I think because the universe has had so many billions of years longer than existence of earth to evolve intelligent life, the chance of us running to aliens that are only within 10,000 or 100,000 years of us would be slim. It would be like if you pick two complete random 9 digit numbers, each between 0 and 6 billion, and you so happen to pick two that only differ by 5 digits.
The odds are in tens of thousands to one against it. So are the chances that the first technological civilization we encounter being only 10,000 or 100,000 years more advanced than we are. I think a good case can be made that the average technological gap between any two civilizations is 2-3 billion years.
As to dumbing down, you only dumb down if there is something in the recipient you can relate to. The fact that you know how things might turn out for the recipient's descendants 3 billion years hence is pretty slim basis for relation. I means do we feel any particular kinship to bacteria? Which would be to us what we might be to the first alien we run into.
The odds are in tens of thousands to one against it. So are the chances that the first technological civilization we encounter being only 10,000 or 100,000 years more advanced than we are. I think a good case can be made that the average technological gap between any two civilizations is 2-3 billion years.
As to dumbing down, you only dumb down if there is something in the recipient you can relate to. The fact that you know how things might turn out for the recipient's descendants 3 billion years hence is pretty slim basis for relation. I means do we feel any particular kinship to bacteria? Which would be to us what we might be to the first alien we run into.
