system
Given the following post, respond as if you're commenting on Reddit:
human
Eli5 Why can't spinal cord injuries (severed) be fixed with some kind of signal repeater?

Like your brain still sends the signal couldn't you attach something to each end so that it relayed the signal to the severed nerve?
gpt
Ok imagine a bundle of 100000 cables thinner than hair and all looking the exact same get severed. Your job is to connect them correctly one by one. How do you know which with which and how do you grab them and reconnect them without further damaging them? If you solve those 3 problems you will be rich.