The brain is a mystery; it has been and still will be. How does the brain produce thoughts? That is the central question and we have still no answer to it.

As followers of natural science we know nothing of any relation between thoughts and the brain, except as a gross correlation in time and space.

If it is mind that we are searching the brain, then we are supposing the brain to be much more than a telephone-exchange. We are supposing it to be a telephone-exchange along with subscribers as well.

Swiftly the head mass becomes an enchanted loom where millions of flashing shuttles weave a dissolving pattern, always a meaningful pattern though never an abiding one...

The brain seems a thoroughfare for nerve-action passing its way to the motor animal. It has been remarked that Life's aim is an act not a thought. To-day the dictum must be modified to admit that, often, to refrain from an act is no less an act than to commit one, because inhibition is coequally with excitation a nervous activity.

This integrative action in virtue of which the nervous system unifies from separate organs an animal possessing solidarity, an individual, is the problem before us.

He solved at a stroke the great question of the direction of nerve-currents in their travel through brain and spinal cord.