Thought Experiment: Talking to the Other Aliens

This is a direct continuation of the previous post, so read that one first if you haven’t yet.  In some sense this post is simpler than the previous, in that it uses simpler concepts and doesn’t involve understanding of the real number system.  But it may be harder for many readers, because I’m asking you to imagine an alien race which does not understand certain things that you probably can’t remember a time when you didn’t understand.  And it’s hard to imagine what it would be like not to know what we know.

It’s interesting, isn’t it, how people are much better at temporarily adding an unfamiliar concept to their working context than they are at temporarily subtracting a familiar one?