I read this short story a few years ago, online, but I didn't save the link, author or title. It was about 5-10 pages long, with the following plot points that I remember:
- A lone human explorer lands on an alien planet. He doesn't leave the ship for days, just sits in the open airlock, apparently doing nothing. The aliens are non-hostile, but are thrown off by the fact that the explorer doesn't make any attempt at contact at all.
- After some time, the human does make contact with the aliens, who are friendly, and present to him their culture and technology. The explorer, however, continuously talks in riddles, both confusing his hosts and making them believe that the human race is more advanced in all fields than it actually is.
- One of the riddles I remember very well: when the aliens are presenting the human some kind of advanced technology, he interrupts with a question like "this is fine, but did you solve why a mouse if it spins?" Which, again, confuses the aliens extremely.
- In the end, I believe, the human leaves the aliens with some kind of peaceful treaty, and of course leaving them wondering about the riddles and jokes. Then, once back on his ship and in space, he starts with renewed effort trying to solve a similarly unsolvable riddle or paradox.
This is it as far as I remember. Unfortunately, I can't provide even approximate date on when it was published, as I read it in some kind of online anthology, possibly a scanned version of a printed magazine.