Just like a good drama, the human brain runs on conflict.

What we find is that our brains have colossal things happening in them all the time.

You are part of a complex social network that changes your biology with every interaction, and which your actions can change.

We are nothing but the product of billions of years of molecules coming together and ratcheting up through natural selection, we are composed only of highways of fluids and chemicals sliding along roadways within billions of dancing cells, trillions of synaptic conversations hum in parallel, this vast egglike fabric of micron-thin circuitry runs algorithms undreamt of in modern science, and these neural programs give rise to our decision making, loves, desires, fears, and aspirations. That understanding would be a numinous experience, better than anything ever proposed in anyone's holy text.

Societies would _not_ be better off if everyone were like Mr Spock, all rationality and no emotion. Instead, a balance - a teaming up of the internal rivals - is optimal for brains. ... Some balance of the emotional and rational systems is needed, and that balance may already be optimized by natural selection in human brains.

There are always wonderful mysteries to confront.

Given the billions of neurons, this means there are as many connections in a single cubic centimeter of brain tissue as there are stars in the Milky Way galaxy.