Found on the net (I forget where):

"The reason a dog has so many friends is that he wags his tail instead of his tongue."

"Dogs need to sniff the ground; it's how they keep abreast of current events. The ground is a giant dog newspaper, containing all kinds of late-breaking dog news items, which, if they are especially urgent, are often continued in the next yard."

"Dogs feel very strongly that they should always go with you in the car, in case the need should arise for them to bark violently at nothing right in your ear."

"A dog teaches a boy fidelity, perseverance, and to turn around three times before lying down."

"No dog should ever jump up on the dining-room furniture unless absolutely certain that that he can hold his own in the conversation."

"In order to keep a true perspective of one's importance, everyone should have a dog that will worship him and a cat that will ignore him."

"There is no psychiatrist in the world like a puppy licking your face."

"The average dog is a nicer person than the average person."

"No one appreciates the very special genius of your conversation as the dog does."

"Did you ever notice when you blow in a dog's face he gets mad at you? But when you take him in a car he sticks his head out the window!"

"The great pleasure of a dog is that you make a fool of yourself with him and not only will he not scold you, he will make a fool of himself too."

"They never talk about themselves but listen to you while you talk about yourself, and keep up an appearance of being interested in the conversation."