**Background and objective:**

*The Number of the Beast* isn't meant to be completely understood on first reading, and that's one if its biggest weaknesses. I read the book having read very little of Heinlein's other works, and found it to be a delightfully eclectic book. 

Instead of attempting to cover all of Heinlein's work as Martha did, I've concentrated on *what books one should read for maximum enjoyment of the four core world-as-myth novels*. I've omitted books that are mentioned in passing as well as books where a character makes a very quick appearance. 

As I said above, you can read these books having read none of Heinlein's other books, but I don't recommend it unless you enjoy uncertainty and opaqueness in your fiction. (I do, as it happens, but I suspect that most readers do not.) 

Familiarity with Heinlein's other works is helpful, as well as familiarity with classics such as the Oz books, the Lensman books, Alice in Wonderland, and the Barsoom books. (I still haven't managed to get through most of those, but I'm familiar with the stories and characters at least a little bit.) 

**Suggested reading order:**

The chart below puts the books in an order that presents one with the "Future History" and standalone books (the green and gray rectangles) before reading the world-as-myth books they lead into (the red rectangles). It also alternates easier books with more challenging ones. However, you can alter this order based on availability of the books, but the arrows in the chart are a guide to what books lead into others. (The core books should be read last where possible.) 

![enter image description here][1]

*Time Enough for Love* is an odd case. While it's part of the "Future History" books, characters in the book are an important part of the story in *The Number of the Beast*. Indeed, *Number* is, in some ways, a conclusion to the story of Lazarus Long. Whether or not *Time Enough for Love* is a core world-as-myth book is unclear, but it's definitely a prelude to the world-as-myth story. (*To Sail Beyond the Sunset* is similarly more a part of the "Future History" story than the world-as-myth story.) 

**Summary:**

If you enjoy works where everything is explained neatly, read *The Number of the Beast* last. However, the books that follow will make little sense, in particular *The Cat Who Walks Through Walls* depends on familiarity with earlier works. However, *Number* benefits greatly from multiple readings, and can be re-read in whole or in part. 


  [1]: https://i.sstatic.net/qrFk2.png