system
A chat on subreddit /r/PoliticalCompassMemes
human
Exactly - our bodies can't actually detect a lack of oxygen, what we experience as "not getting enough air" is actually just an excess of carbon dioxide. So if you replace oxygen with an inert gas like nitrogen while keeping carbon dioxide levels low, people will just slowly suffocate without noticing. That's why you need oxygen monitors in say facilities handling large amounts of liquid nitrogen or helium.
gpt
You're body does actually have a hypoxic drive it just doesn't normally use it it's the backup. It is what drives people with severe copd to breathe though because their blood acidity sensors (what a normal healthy person uses to determine when to breathe) get burned out basically. Interestingly, in rare circumstances if a person with copd achieves 100% oxygen saturation it can cause them to stop breathing entirely.