If Spider Robinson used that quote, I presume my text searches of archive.org would have found it. Yet across the different search combinations, I only found a dozen-odd books, none by an SF author.

Why do you associate it with something written by a famous author?

I don't see anything which suggests its a well-known phrase. Google and DDG together found fewer than 100 pages using that quote. Most appear to have been spontaneous creation. One attributed it to "a Norwegian friend."

(This all assumes my search terms were meaningful.)