A Slice of Life: Breakfast Conversation

My son and I have this great morning routine where we sit and talk at the breakfast table while he eats. This morning's breakfast conversation between us went something like this...

"Well, mom - how are you doing?"
"Okay. I have a paper that needs to be turn in today."
"Is that why you woke up early?"
"Yep, I started thinking."
"Mom, you know your brain needs rest. You should have stayed in bed."
"I couldn't. My brain was awake."
"Oh, mom. that's your brain. You need to learn how to quiet your brain."

How does my son know this already?