This recent article on Slate raised the interesting spectre of civil or criminal action in response to parents failing to vaccinate their children. The issue being one of contributory negligence. If a child were to become ill due to exposure from an unvaccinated child, does the parent of the now ill child have recourse against the parents of the unvaccinated child?
It is somewhat ironic that “proving cause and effect will sometimes be difficult” for any such case, because proof of cause and effect is exactly what brought about this situation in the first place. What astounds me is that a lot of people who write about this gulf between the reality of cause and effect, and the anti-vaxxers’ understanding of it miss so many obvious sources of these misunderstandings.
Humans are naturally pretty bad at dealing with ratios, and we will unconsciously give additional weight to different types of emotional content, sometimes flying in the face of strongly contradicting but ‘sterile’ evidence. Why not understand where the vast majority of these misunderstandings come from?
In the case of the MMR/autism ‘thing’ (not calling it a controversy), it’s easy to see why people who are ‘in’ the situation of noticing that their child has just been diagnosed with autism, and remembering that the last major medical event in their child’s life was the MMR vaccine, might intuitively link the two. (Note that MMR is given at age two, and that is the age at which it first becomes possible, as the science currently stands, to diagnose autism.) The perpetuation of the MMR/autism ‘thing’ has nothing to do with mercury in the manufacturing process or any of the elements of Wakefield’s original “study” – it is post hoc rationalisation of an intuitive belief using conveniently available “science” – in quotes because Wakefield failed to disclose the source of the funding for his study. He has since been struck off the medical register.
Further, it’s easy to see why people who have not had such a diagnosis might be more inclined to notice the emotional story of someone who has (whether they themselves cite the link, or not), and place that information above the science that says otherwise. We are ultimately egocentric organisms, we will often place our own experience ahead of conventional wisdom, especially if that conventional wisdom comes to us with no emotional content (and sometimes that’s absolutely the right thing to do). When we’re not more egocentric we’re more social, and that means that many of us will place another person’s emotional information ahead of clinical information.
This goes to a bigger problem, that because science very often removes the human face from the information, a lot of people simply can’t relate to it. Recall, as well, that many popularisers of science – those that can humanise it, Carl Sagan springs to mind – face a backlash of sorts from the scientific community. Those involved in the hard sciences don’t want to see it reduced to one of the humanities (yet at the same time wonder why science isn’t a more popular choice at school and is under-represented in politics). Psychology typifies this battleground as it is a science that many of the natural sciences don’t see as one because it’s too “soft,” because it is too human.