Much like any other machine, the human body is made of a list of discrete organs.
Many of these organs are easy to replace (these days), and some are more difficult. We can transplant a kidney, for example, but transplanting an eye is not yet possible.
As we learned to transplant more organs, we ran into limits – those organs need to come from somewhere. There are not enough donors to satisfy the demand.
And so we learned to replicate the functions of many of these organs artificially. At first, with large external machines, but eventually much smaller embeddable devices much the same size as the originals.
We have learned to 3D print replacement organs, from hearts to bones. We can build heart “scaffolds” that start pumping on their own as they develop.
We can almost build prosthetics that are as good as the originals. A recently developed artificial hand, for example, has all of the movements of a biological one, and can even sense touch and heat and pass that information to its owner through nerves.
We have discovered in some ways that some prosthetics are even better than the original. When a leg-amputee easily won a race against fully-limbed opponents by using prosthetic “blades”, there was a call to ban the use of prosthetics in that race in future.
In the future, we will be able to create organs that are much better. Imagine, for example, replacing your eyes with eyes that can switch to different frequency ranges, to see at night using heat for example, or even to see remotely through someone else’s eyes.
Imagine adding a second heart. Or replacing the heart altogether with a series of discrete pumps around the body.
In this chapter, we'll look at various organs and the current state of transplant or prosthetic technology with regard to those organs.