However, my dog is orders of magnitude smarter, and has taught herself:
- Lying. She barks "at the mailman" about 10 minutes before he arrives, so I'll put her out when he's in the area
- Mirrors. She understands that her reflection is only a reflection, and will look at herself to see if her fur is ruffled on her hindquarters
- Language. Dogs are often taught to communicate with buttons that trigger a word. The conventional wisdom is that it takes a dog about a week to learn to use them. She taught herself 5 separate buttons in 20 minutes, and uses them to this day, chaining them together to express her thoughts remarkably clearly. For example, she used "no" + "time for bed" in the morning when I hadn't refilled her water yet.
But that's why dogs are so popular: they're calibrated to our psyche. They understand human gestures incredibly well.