Great Minds Buy The Same Books?

LibraryThing has an excellent feature called "Legacy Libraries". It is a project in which people index the libraries of dead historical figures, where the contents of such libraries are known. You can then compare your library with theirs.

Here are some examples of overlap:

I share 6 books with John Adams.
I share 32 books with Walker Percy.
I share 9 books with Thomas Jefferson.
I share 37 books with Ernest Hemingway.