OK, thank you guys. It's clear now, more or less. It is usually not a problem to guess the meaning of the word; the mood and expression is what was interesting.

I thought before it was a bit old-fashioned expression... But now I'm reading Hynline's "Stranger in a Strange Land", and he uses "why" virtually on each page, out of the mouth of every hero, in any situation That's why it stuck my mind.