By that definition there is literally no substance in existence that has been proven safe. Because the definition of safe is that no experiments have been able to demonstrate danger.
You know that you can’t prove a negative.
I know that you can’t prove a negative.
Probably most people on HN know that you can’t prove a negative.
But when a person who doesn’t spend their time nerding out on science goes to the doctor and hears, “the substance is safe”, it is not a guarantee that they know that you can’t prove a negative. If you can’t be sure that your audience knows that it’s not possible to prove a negative, then you should be pretty cautious with your words.
Safe, in the context of living on Earth, means an acceptably low risk of a bad outcome.
Tylenol is safe. Tylenol can also permanently damage your kidneys.
Walking is safe. Walking can also permanently damage your cartilage.
Food is safe. Thousands of people die from choking.
We all know this, colloquially. When it comes to medicine, it is as if one's brain hops and skips right out of their ear. It's not magic, it works like everything else on Earth works.
I think there is a non-insignificant number of people who would understand the word safe as no risk, who if something bad happened to them after submitting themselves to such a safe procedure, would find themselves deceived. Technically, I think they would be correct. Therefore, it should be explained that there is a risk but that it is on some order that they can relate to, like the risk of walking down the street.
A doctor will 100% explain that a procedure has a risk. They will say something like this procedure is “generally safe” but there is a very small risk of complications. Then they will make them sign a consent form spelling out those risks.
> I think there is a non-insignificant number of people who would understand the word safe as no risk, who if something bad happened to them after submitting themselves to such a safe procedure, would find themselves deceived.
These people are then dishonest, because they know, deep down in their heart of hearts, this is absolutely not what safe means.
Again, everyone agrees eating an apple is safe. It's even good for you! But they also know every time they take a bite, there is a risk that they can choke and die. They know that. I know that. You know that. Everybody knows that.
Colloquially, even to the most naive, we know that zero risk does not exist, and that "safe" merely means "an acceptably small amount of risk". If we are changing our definitions based on the context, for example, everything on Earth and then medicine, that is dishonesty. If we are dishonest to ourselves, then we are delusional.
You can’t prove a negative.