The human brain is the most complex structure in the known universe for its size (Figure 6.1). It has more nerves than there are people in the world, or devices on the Internet, so how did it come about?

A bee’s brain is just a sliver of neurons, but it can fly, form colonies, and communicate better than any equivalent robot, and nature didn’t stop there. It evolved big brains like ours from tiny brains like theirs step-by-step over hundreds of millions years, so all brains, including ours, can grow from small beginnings.
QR6.2.1 Brains Grow
QR6.2.2 Decentralization
QR6.2.3 Hierarchies
QR6.2.4 Autonomy
QR6.2.5 Three-Center Theory
QR6.2.6 The Emotional Center
QR6.2.7 The Intellectual Center
QR6.2.8 Sharing Control
QR6.2.9 The Binding Problem