The objection
"We shouldn't reduce animals' suffering, because suffering is useful to them."
When suffering is useful
It's true that pain is sometimes useful. It warns that something is wrong and makes the animal move away from danger. Feeling the pain of a burn makes you pull your paw out of the fire.
But not always
Suffering is only useful when the animal can use it to be better off, for example to avoid a bigger harm.
In nature, a lot of suffering does nothing like that:
- a baby animal that starves a few days after being born doesn't learn anything from the hunger;
- an animal with an incurable disease suffers without being able to do anything about it.
Even when it's useful
And even when suffering is useful in some way, there are reasons to prevent it if the same benefit can be had some other way. For example, if we can protect the animal from danger without it having to get burned first, that's better.
Think about humans: a toothache warns that something is wrong, but nobody says we shouldn't use anesthesia at the dentist.
In short
- Suffering is only useful when it helps the animal be better off.
- Much natural suffering is of no use at all to the one who suffers.
- If we can get the benefit without the suffering, it's better to prevent it.