Animals are dumb.
You want to know what dogs think? Three primary things: poop, eat, and play. So when your dog looks up to you with his cute eyes, don't lie to yourself. Fido isn't thinking "Gosh, I love you master!" Your best friend is thinking "Poop! Eat! Play!"
The Internet loves photos of adorable animals combined with whimsical captions. Ha, ha, animals think just like humans! Only they're not like humans. They're not human. Critters have tiny brains that can only process simple thoughts. If you can even call their instinctual impulses "thinking."
Hate to break it to you, but this is what actually knocks around the noggins of cats, monkeys and bears. This doesn't make them any less adorable.