Why can’t we control out own sensations ? Why is our brain not able to just turn off the feeling of pain for the moment ? “I got it, something is bad, now stop hurting !” Or to just fall asleep whenever we want to.
In: Biology
There’s nothing in an absolute sense preventing those things from existing, but they have to happen through the evolutionary process. The pain mechanism and response system evolved in this way, and it has huge evolutionary advantages. Bluntly, most of the time, or at least enough of the time to favor reproductive success, having a persistent pain signal that can’t be turned off leads to more offspring. The exact reasons why this is the case aren’t all that critical, but it’s probably something along the lines of if you learn to avoid things that cause pain, you’ll do less damage to your body, and likely survive to be able to reproduce. At least more often than those without any sort of pain and response mechanism. So now to be able to turn off the pain signals, the body would need to develop and pass along some way to do that. It would have to be something genetically coded in, and it would have to confer a survival advantage resulting in more offspring compared to not having that ability. It’s not enough that we’d want that ability, it would have to impact our ability to pass on genes. Same with being able to sleep or not sleep as desired, or just about any physical or behavioral trait for that matter.
/edited for typos
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