system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: When somewhere on our body got injured like cut or bruised, why can’t our brain just switch off and keep the nerves idle on the injured area temporarily so that the person won’t feel any pain?
gpt
That would just increase your chances to injure yourself again.  
Pain serves a very important function: **"There is something seriously wrong here!"**, and, by extension via operant conditioning: **Better not do that again!/Better stop doing that!"**.  
  
From an evolutionary perspective you could say that pain responses increase fitness, as they have a higher change of getting passed to the next generation. A human without pain responses will quickly leave the gene pool.