The phrase has a few distinct readings, and each one is true in a different register.
Biological
At the most basic level, pain is a feedback signal — the nervous system’s mechanism for learning what to avoid, what to protect, where the boundary is. Without it, the body can’t regulate itself. People with congenital insensitivity to pain sustain devastating injuries because that loop is broken. They have no way to know when something is wrong until the damage is already done.
The system that pain feeds here is the self. Remove the signal, and the organism loses the capacity to defend itself.
Institutional
Scale it up and it gets darker. A lot of institutions don’t just tolerate pain — they depend on it. Healthcare systems that profit from illness. Criminal justice built on punishment rather than repair. Economies that require exploited labor to function.
In these cases the pain isn’t a bug. It’s the input that keeps the machine running. The system was designed around it, or evolved to require it, and operates well precisely because the pain is reliable and ongoing.
Personal
Trauma can wire you into patterns — hypervigilance, people-pleasing, overwork — that function like internal systems sustained by old pain. They were survival mechanisms once. They worked. But they keep drawing from the same well long after the original threat is gone, because the pattern doesn’t know the threat is gone.
This is the subtlest case because the system being fed is you, and the pain is also yours. The line between coping and self-consumption is hard to find from the inside.
Creative
Suffering genuinely does generate something. Art, empathy, insight. Not because pain is noble or necessary — it isn’t — but because humans are meaning-making creatures and pain is raw material that demands to be processed. The alternative to processing it is carrying it.
This reading is the most easily romanticized and therefore the most dangerous. The output is real. That doesn’t make the input good.
The question the word “feeds” raises
The unsettling part of the phrase isn’t pain — it’s feeds. To feed a system is to sustain it. To be the input it needs in order to keep running.
Which raises the actual question: which of these systems are worth preserving, and which ones should we let starve?
The biological one, yes. The personal ones — sometimes, carefully, with the goal of eventually making them unnecessary. The institutional ones that run on suffering — probably not. The creative impulse — yes, but ideally from a source other than active pain.
The phrase doesn’t answer the question. It just makes it unavoidable.