Will Robots Inherit the Earth?
The brain, like other finite things, must reach some limits to
what it can learn. We do not know what those limits are; per-
haps our brains could keep learning for several more centuries.
Ultimately, though, we will need to increase their capacity.
The more we learn about our brains, the more ways we will
find to improve them. Each brain has hundreds of specialized
regions. We know only a little about what each one does but
as soon as we find out how any one part works, researchers
will try to devise ways to extend that organs capacity. They
will also conceive of entirely new abilities that biology has
never provided. As these inventions accumulate, we will try
to connect them to our brains perhaps through millions of
microscopic electrodes inserted into the great nerve-bundle
called the corpus callosum, the largest data-bus in the brain.
With further advances, no part of the brain will be out of
bounds for attaching new accessories. In the end, we will find
ways to replace every part of the body and brain and thus
repair all the defects and flaws that make our lives so brief.
REPLACING THE BRAIN
Almost all the knowledge that we learn is embodied in vari-
ous networks inside our brains. These networks consist of
huge numbers of tiny nerve cells, and even larger numbers of
smaller structures called synapses, which control how signals
jump from one nerve cell to another. To make a replace-
ment of your brain, we would need to know something about
how each of your synapses relates to the two cells it bridges.
We would also have to know how each of those structures
responds to the various electric fields, hormones, neurotrans-
mitters, nutrients and other chemicals that are active in its
neighborhood. Your brain contains trillions of synapses, so
this is no small requirement.