Aliens and Trade

Krugman suggests extra-terrestrial life would be good for trade. I imagine (if we survive the encounter) the bigger boost will be from technological development, but still a good point.

The same would be true, of course, for a human colony on Mars - division of labor is the foundation of civilized life.

But the trade would be very different - we'd probably be trading actual goods to Mars, but I doubt we would get goods back. The ones we would send would have to be absolutely essential, too, because of the cost of the trip.

So what would we trade? Knowledge. I imagine the early Martian colonists will do three things, for the most part: farm, build, and produce knowledge (maybe mining too if it turns out there's anything worthwhile up there). Knowledge is cheaper to send back to Earth than anything else, so it will likely play an important role in interplanetary trade a century or two from now (if we don't at least have a consistently manned outpost there before I die I'm going to be extremely disappointed).

Lovecraft talked some about extra-terrestrial exchange (not always voluntary, of course) when he wrote his alien stories. What was traded with the Yithians? With the Mi-Go? Knowledge.