What really knocks me out is a book that, when you’re all done reading it, you wish the author that wrote it was a terrific friend of yours and you could call him up on the phone whenever you felt like it.
~ J.D. Salinger : Catcher in the Rye (1951)
Do you feel like that when you’ve just read a good book? And by “good book”, I 
mean one you really enjoyed. It doesn’t have to be great prose, it just has to say something to you. It has to challenge you, or tickle you, or even just keep you company. You know it when you read it.
I once had a conversation with a friend about what makes good beach reading. My friend asserted that the best book in that situation is one that’s a little fluffy, one that doesn’t make you think too much. A book you can pick up and put down as you please. I get that, but I prefer a meaty book in that scenario. On the beach, you presumably have the free time to engage your mind without worrying about a thousand other things. But never mind, it’s all personal preference.
I think that the author who writes about what speaks to him or her personally, whether it be what fascinates, delights, or challenges, is an author that will have many unknown friends.
