"A pearl may in a toad's head dwell, and may be found too in an oyster shell."
-- John Bunyan, Apology for his Book

Old folklore said that the toad carried a magical gem in its head that was an antidote for poison. (These stones were really the fossilized teeth of an ancient fish.)

This quotation is from John Bunyan's very long and convoluted forward to his book, "The Pilgrim's Progress." To me, the purpose of this 235 line apology (as he calls it) is to say, "Please give my humble work, written by a humble man, a try - you may find some unexpected good in it."

With this reference to a pearl in a toad's head Bunyan suggests that the reader may find something of value (the pearl) in his book (the toad), as they might in a book by an author of more renown (the oyster.)

In other words, don't judge a book by its cover.

"It is wiser to find out than to suppose"
-- Mark Twain

If I had to pick a personal motto, this quotation would in my top 5 finalists.

As a child, I loved to browse through the volumes of the World Book Encyclopedia. My reference library overflows its shelves, and the books are full of little paper bookmarks. "Finding out" may be wise, but it can also be an exciting journey to unexpected places.