I understand that it's not maybe intended to be a jerk or has the deeper purpose of getting someone to rethink their position more carefully. But it's just a bit of a jerk-ish way to do so (in my view) - one that may be perceived as an attack on someone's intelligence and critical thinking abilities. It sets people on the defensive.
I try to take a more-flies-with-honey method myself - challenge the person to go through this process positively, and having demonstrated that you have tried to understand their viewpoint. It may make them more likely to understand yours, too.
As others have said and I hinted at, there are some things where societal benefit may and should outweigh individual belief. Laws are not always the most effective, or only way, to achieve these ends. Education is valuable.
>Maybe, but there's probably something to be said for social cost that make that argument somewhat less valid. Herd immunity. Seat belt and helmet laws, etc. Note that I am not taking a position here on vaccinations or anything else, just that it's not the best point one could make (other than for some casual amusement at cognitive gear grinding and confusion). It'd be the same as making fun of someone with anti-abortion views by saying "but death penalty lol isn't all life valuable!?" - which I am certain many have said and heard, but this type of arguing doesn't actually approach the reality behind issues and beliefs and positions.
The purpose isn't to be a jerk. The purpose is to cause anyone to pause and think through their position more thoroughly. What rules should apply, when and when not. Without searching more deeply for a more principled position it will come down to "because that's how I feel". But that's not how someone else feels. And what makes one person's feelings more important or superior to another's?
So, when does society get more say than you over your body?
Personally I don't think we should use and rely on the law to try to legislate away stupidity. We should use compassionate education. Yeah, I know, it sucks we have to be patient and not everyone will get on board. The only other option is to imprison and kill all the people that don't agree with you.