> The difference between monkeypox and smallpox is arbitrary?
All differences between two things is always arbitrary. This is something I wish more people understood. Two different things are never the same thing. You can come up with similarities based on arbitrary criteria, and that's all.
For example, what we consider make two different person a woman is arbitrary criteria that we just all agree on, or debate forever.
> How many people are dropping dead from it? It doesn't seem like an arbitrary distinction to me
You want to engage in that "forever debate of semantics", but I don't think that's your point.
Currently, it's agreed on taxonomy that chickenpox is not on the same family as monkeypox and smallpox. That's just agreed upon arbitrary categories.
Now the arbitrary doesn't mean useless. Often categories are chosen based on some practical aspect. For example it helps to group them if they have a similar behavior in some way that is often helpful to group in the default case.
An example of this is how in culinary science, a Tomato is made a Vegetable, because it's more useful to club vegetables around their flavor profile. You most of the time don't want to use a Tomato for a recipe that calls for fruits. But in botanical science, flavor isn't useful, it's more useful to think in terms of what contain seeds, thus a Tomato is made a fruit.
Each science uses their own arbitrary classification based on what is more practically useful for their line of research.
Ok, so I think your point isn't to try and tell virologists that their chosen taxonomy isn't as optimal for their line of research. But that in the case of public policy and messaging, virulence might be more important.
Even though both virus are of the same family, there is still a major difference in their virulence. And maybe that property holds more weight in this case.
I think that's a great point, but that you were arguing wrong by attacking the definition instead of bringing up the characteristic of importance and explaining why.
Now this is as much as I know of virology, so I can't say if there are good reasons to be worried about the chances of virulence changing because they are in the same family or not. But I'd say you're right, virulence is what the public cares about, and it be nicer for virologist to explain the chances of the virulence getting worse through some mutations and if they think it's high, why, or if they think it's low, why.