If you pick up a starving dog and make him prosperous, he will not bite you.
This is the principal difference between a dog and a man.
(Mark Twain)

Outside of a dog, a book is a man's best friend.
Inside of a dog, it's too dark to read.
(Groucho Marx)

The Unknown
As we know, there are known knowns.
There are things we know we know.
We also know there are known unknowns.
That is to say we know there are some things we do not know.
But there are also unknown unknowns, the ones we don't know we don't know.
(Donald Rumsfeld)