The concept that helped me most understand my own body was realizing the signal and the system are separate. In your car, the oil light is almost entirely separ

The concept that helped me most understand my own body was realizing the signal and the system are separate. In your car, the oil light is almost entirely separate from the actual oil system. It's the same with our body. Feeling tired is separate from being tired. Feeling hungry is separate from being hungry. Drugs work like putting electrical tape over a low oil light. Amphetamines and even caffeine are good at blocking out the signal. The underlying issue is still there. But, sort of like you said, the signal comes really early. It's like a low fuel light that comes on when you get to a half tank.