How we cite our quotes: (Chapter.Paragraph)
Quote #1
…. (a Hooloovoo is a super-intelligent shade of the color blue). (4.22)
We pulled this quotelet because The Hitchhiker's Guide is full of new things for us to experience. It is, in the best sense, a mind-expanding experience where we have to wrap our heads around new concepts, like a life form that's a color. We don't quite get it, but we love that it's wearing a prism as formal wear to meet the president.
Quote #2
Arthur prodded the mattress nervously and then sat on it himself: in fact he had very little to be nervous about, because all mattresses grown in the swamps of Squornshellous Zeta are very thoroughly killed and dried before being put to service. Very few have ever come to life again. (5.51)
Even pretty simple words like "mattress" hold whole new meanings out in the galaxy. (And so does the word "killed," by the way. Usually being killed is permanent, but at least a few mattresses have come back to life according to this quote.)
Quote #3
Ford, with a lightning movement, clapped his hand to Arthur's ear, and he had the sudden sickening sensation of the fish slithering deep into his aural tract. Gasping with horror he scrabbled at his ear for a second or so, but then slowly turned goggle-eyed with wonder. He was experiencing the aural equivalent of looking at a picture of two black silhouetted faces and suddenly seeing it as a picture of a white candlestick. Or of looking at a lot of colored dots on a piece of paper which suddenly resolve themselves into the figure six and mean that your optician is going to charge you a lot of money for a new pair of glasses. (5.110)
Just as it's hard to express the absurd or the amazing, it may be hard to describe the totally new. So here, the experience of the Babel fish is compared to figuring out an optical illusion or to taking a color-blindness test, experiences that we are probably familiar with. (And we might be familiar with paying the optician money for new glasses, even though we just got new glasses.)