Mahmoud looked very thoughtful. "No.  Not really. 'Grok' is the most important word in the Martian language - and I expect to spend the next forty years trying to understand it and perhaps use some millions of printed words trying to explain it.  But I don't expect to be successful.  You need to think in Martian to grok the word 'grok.' Which Mike does and I don't.  Perhaps you have noticed that Mike takes a rather veering approach to some of the simplest human ideas?"