Who's to say her ideas are wrong? In fact, what if you're ideas here are wrong? Should you be culpable for trying to convince us? Who determines if her ideas are wrong or right? I've heard evidence that in the majority of published math papers there's at least one major flaw in a proof of each paper. Are they now culpable, as are the publishers?
Effectively what you're arguing is that everyone should refrain from making any statement (opinion or fact) unless they're stating something that is universally agreed by some body. It sounds like you're describing is the church of days past.
I much rather live in a world/country were people are free to say what they like, and I'm free to believe it or not -- with only certain rare exceptions (for example judges, in their capacity as a judge, shouldn't lie).
I'm quite ready to say that promoting abstention from vaccination because it causes autism is wrong. There is no scientific evidence for such a claim. And, if you read The Ethics of Belief, you will find that my view is completely at odds with the position of the church - I do not recognize "faith" as a legitimate basis for believing something.
I'm not really sure where you are going with a statement like "Who's to say her ideas are wrong?". It sounds like moral relativism, but I don't want to assume that is what you intended unless you explicitly say so. I assume you agree that people can have ideas that are wrong (e.g., 2+2=5, "the world is flat", etc.), and that other people are justified in pointing out that those ideas are wrong. If my assumption is correct, then you are either saying that these particular ideas are not wrong, or you are saying they are wrong but that Jenny McCarthy and Oprah should not be held culpable for promoting them. I'll assume the latter.
To be clear, I am not saying people should refrain from making any statement unless it is universally agreed upon. I'm saying that before believing something (and trying to spread that belief to others), we have a duty to investigate our beliefs and subject them scientific scrutiny. Failure to discharge that duty injures society. Given the lack of scientific evidence of a link between vaccination and autism, one must conclude that Jenny McCarthy (and by extension, Oprah) has either failed to subject her beliefs to such scrutiny, or willfully ignores evidence to the contrary. In my opinion, this does constitute some degree of culpability.
Effectively what you're arguing is that everyone should refrain from making any statement (opinion or fact) unless they're stating something that is universally agreed by some body. It sounds like you're describing is the church of days past.
I much rather live in a world/country were people are free to say what they like, and I'm free to believe it or not -- with only certain rare exceptions (for example judges, in their capacity as a judge, shouldn't lie).