Ah OK

But does this mean that anyone can see that all of the addresses in my wallet belong to one person?  If you know one of my wallet's addresses, can you find the rest of my wallet's addresses?

Edit: Nevermind, I found a description of how it works here: https://en.bitcoin.it/wiki/Deterministic_Wallet  I see that depending on the algorithm used to generate key-pairs, it can be difficult to find the root key & chain code from a given public key.

Actually, I'm very impressed by this.  I was under the impression that I needed to print a new paper wallet each and every time I created a new key-pair, but now I see that my root key and chain code never change, so I only ever need 1 paper wallet.