We don’t know whether the blanket is effective on dogs. Learning that if it’s effective on dogs, it’ll be effective on other animals doesn’t help establish that it’s effective on dogs.

If magnets can intensify messages from nerves to the brain, that suggests pain might be intensified. Alternatively, there’s no clear relationship between pain reduction and transmission of messages from nerves to the brain.

The argument concerns whether magnets are a way to alleviate arthritic pain in dogs. The number of other ways available to do this has no effect on whether magnets can alleviate arthritic pain in dogs.

This suggests potential limitations on the effectiveness of magnets to treat humans.

This shows that a control group didn’t experience pain reduction in the same proportion as the group that got the magnets. This helps to eliminate the possibility that the pain reduction in the magnet group was due to something everyone had in common.