Nehaveigur

Out of Kevin Kelly’s twelve assumptions for extraterrestrial life, I agree with the first nine.

However, he gets his tenth, and most important, assumption wrong:

10) The only reason for an advanced civilization to visit another planet is to see if there is another civilization which has invented things it has not, and perhaps could not invent. Invented resources are thus unlimited in scale and scope, and can be discovered only in unique places in the cosmos. Interstellar travel is essentially not travel through cosmic space but travel through possibility space. You visit another planet to visit other possible minds to see if they have thought of fabulous technologies your collective minds cannot reach.

Even if almost all civilizations adhere to this, it takes only one that doesn’t to make this point invalid. A spreader civilization would take over an increasing number of star systems and resources, eventually becoming more common than the non-spreaders. Whether there’s something to gain from spreading is beside the point and assuming that this wouldn’t happen is equivalent to ignoring evolution. As a result, most civilizations visiting us will be spreaders and scout for whether we’re a good place to settle, invalidating Kelly’s eleventh assumption as well:

11) Every day a few probes of these billions of interstellar civilizations visit our planet scoping out our technological state. These technological probes appear briefly in order to see us, and disappear once they have inspected our inventory. So far we have little to offer; nothing that can’t be found on millions of other planets.