"In the hours that followed, I learned that Ademic hand gestures did not actually represent facial expressions. It was nothing so simple as that. For example a smile can mean you're amused, happy, grateful, or satisfied. You can smile to comfort someone. You can smile because you're content or because you're in love. A grimace or a grin look similar to a smile, but they mean entirely different things. Imagine trying to teach someone how to smile. Imagine trying to describe what different smiles mean and when, precisely, to use them in conversation. It's harder than learning to walk."