I agree with Professor Smith. The only thing I would add may be obvious and may be something you've already tried. It sometimes helps to have third parties intervene to provide all the facts and arguments you would use to try to persuade your wife to change her mind. Here, your knowledge of who might influence her is useful. Would she trust your family's pediatrician or react harshly against him/her as a member of the 'vaccine conspiracy'? Her parents or yours? Mutual friends? While an 'intervention' would be extreme, making friends and family aware of a serious issue that affects the health of your children (and others) and enlisting their help might make it easier for your wife to back down without feeling pressured to do so solely by you. But should these methods fail, then Prof. Smith's suggestion seems appropriate.
Over the past few years, my wife has become a staunch antivaccinationist. (We have a son on the autism spectrum; she has bought into the discredited vaccine causation theory of autism.) She is unreachable on this topic; no facts or reason will move her from her position. Unfortunately, she has decided that our children are to have no further vaccinations. She will not compromise on this. I, of course, want our children to be protected from dangerous diseases and thus want them to be vaccinated. My question: What are my ethical obligations in this situation--to my wife, to my children, and to society? Going behind my wife's back and having the children vaccinated without her knowledge does not seem ethical. Agreeing to her demand that the children receive no further shots also seems unethical--this would put my kids at risk of disease, as well as other people. Telling my wife up front that I'm taking the children to get their shots, despite her objections, also seems problematic--they are her children also. What are my best choices here?