This gets my vote. My hunch is that intelligent life like the kind we would love to meet happens either on the order of once or twice per galaxy during the galaxy&#x27;s entire lifetime, or it happens SO rarely that, if the universe is infinite in extent, then any intelligent observer looking out from the &quot;center&quot; of their observable universe will most likely be in the only intelligent civilization in that visible radius.<p>Depressing, but it seems more plausible than things like &quot;Great Filters of DOOM&quot;. It would predict that there is a lot of intelligence in the entire universe, but each cluster of intelligence is profoundly alone.