One hundred trillion. It’s about the size of the global money supply (called “broad money”), the bacterial count of the human microbiome, and the number of transistors in a supercomputer. It’s also approximately the number of neuronal connections in the human brain.

Connection has an exponential, multiplicative power to create complexity. It’s where the meat of the hardest problems—like consciousness—lies. It can also make problems harder than they first seem to be.

Glial cells, which make up a significant chunk of the brain’s cell count, were, until recently, thought to simply be insulation for neurons. Now we understand that they communicate with each other and with neurons, increasing the complexity of the brain’s map even further. One hundred trillion is just the beginning.

Welcome to “Connections.”