The brain cake

We inherit three brains from our ancestors. Picture them as a three-layered cake.

At the bottom — the ancient reptilian department (the brainstem), focused on survival. It runs the basics: eating, protection, reproduction, fight-or-flight. It keeps you alive and doesn’t ask permission. When there’s no immediate threat, it stays quiet and passes the signal up to the next level.

The middle layer — the monkey brain (the limbic system) — works as an analyzer. It takes the signal from below and checks: is there real danger? If not, it files it away. The monkey watches patterns, forms bonds, feels before it thinks. This is what keeps us together and lets us build civilizations.

What truly sets us apart is the top layer — the human brain (the neocortex). This is where you, the boss, reside. Dreams, language, abstract thought, planning. The part that lets you appreciate beauty and wonder at the world.

A baby grows through all three in order. First the reptile handles survival. Then the monkey wakes up as the child starts feeling and remembering. The neocortex comes last, as the child learns to think and imagine. The reptile breathes, the monkey worries, the human plans. You are all three.

But there’s a flipside. Fear. It whispers caution, reminds us we’re vulnerable, pushes us to guard what we have. And makes us want what others have.