What Books Make One Great?

A blog I love following, and a great question: What books make one great?

“This book is the only book you need to read in your whole life. It has everything a book should have: large words, clever witticisms, a sweeping plot which is really an analogy for the whole of society, riveting characters, popularity with critics and scholars, and lots of pages.”
“But does it have pirates?” the boy said.
“Oh, no. Pirates are not literary enough for a book this grand.”
“Does it have dinosaurs?” the youngest girl said.
“Oh no. Dinosaurs are not symbolic enough for a book of such importance.”
“My book has pirates riding dinosaurs into space,” said the middle girl.
“Ooooh,” said the the boy and youngest girl as they leaned away from their eldest sister and read as Captain Platticus wrangled an interstellar triceratops.