I'm not saying I want to be one. But here's how it will happen.
Nanobots are the size of a skin cell. Bill Gates, et al. will find a way to use them to fight disease, soothe the nervous system, repair brain damage, you name it. Sounds like a good deal. I'm in.
Then soon nanobots will be used to replace cells. They function and divide just like organic blood cells, replicating the DNA of the cells they're replacing. Your kidney stopped working? Nanobots rebuild it, slowly replacing the organic cells that are flushed out. In a month, you have an artificial kidney that works like aces.
Nanobots now target the brain. They repair damaged tissue, restore healthy synaptic pathways, activate creative and intellectual byways. And since they're nanobots, you don't need to buy a computer.
YOU ARE THE COMPUTER.
Want to send a text? Just think it at me. Want to speak Japanese? Download it from Rosetta Stone. Want to play guitar like Jimi Hendrix?
Nanobots put you in complete control of your nervous system. You no longer need to feel unnecessary pain. Addiction no longer exists. Overeating is a thing of the past. Reprogram your taste buds and broccoli tastes like tenderloin. Broken bones heal quickly and flesh wounds rapidly vanish.
Don't like feeling agitated? Depressed? Angry? Ancient history, we now control our emotions. We decide what we want to feel... curious, happy, joyful, courageous. We are whatever we want to be.
Here's the problem.
At what point do you become a machine? When do you cease to be real? 25% nanobot? 50%? There are people today with artificial legs, ears, hearts... are they less human?
The bottom line: Who am I?
We need to ask that question every day, every breath. Am I my body? My thoughts? My emotions? If I decide what I want to feel, who is deciding that?
In The Discovery of Socket Greeny, I posit a future of nanotechnology that spawns a new race of duplicates: nanobot-humans that view organic humans as imperfect and cancerous. They make the argument that God created humankind in His image and humankind created the duplicate. Therefore, God created the duplicate race.
Move over, human. Evolution works that way.
For more speculative science-fiction regarding nanotechnology, check out Post-Human by David Simpson and Feed by MT Anderson.