This seems to be the way our brains naturally work. If we didn't model the world with a mental construct resistant to change, we probably wouldn't have survived very well. But science and rationality are all about minimizing the effect of this tendency, and I would hope that's something we aspire to.
Of course, we see this faulty arrangement very blatantly in Creationism. Step 1: Assume God created the world as told in Genesis. Step 2: find evidence that appears to support this conclusion.
But I see this all too often in the alternative parenting world. Step 1: Assume breastfeeding is totally sufficient and perfect. Step 2: find some way to twist or ignore evidence that babies might need Vitamin D supplementation.
Most recently, I'm seeing some troubling tendencies from Nancy Mohrbacher, the author of the new reference book used by LLL Leaders. She has come out against swaddling. And she hasn't done it in a terribly thoughtful way, laying out what the benefits are or were perceived to be, and comparing new information that may advise caution or revision of our use of swaddling. Nope. Swaddling is Evil seems to be the message, and she is willing to be disingenuous in supporting this conclusion. In her initial post, she notes that "While swaddling may be helpful when used occasionally, routine swaddling during the first months associated with greater risk of . . . SIDS in prone sleeping positions."
Now, in my experience, most people do not understand the word "prone," mistaking it to mean "lying down." It actually means lying face down (supine refers to lying face up.) So I find this misleading, possibly intentionally. And of course, we already know that sleeping face down is a huge risk factor for SIDS. Telling people they shouldn't swaddle their prone-sleeping infants is like telling people to buckle up when they drive drunk.
This really irritates me because maybe swaddling is something we should rethink, but if you try to manipulate me with misleading statements, it's just going to make me want to discount everything you say. And more generally, I think a balanced, empathetic approach that allows for the feelings and beliefs of the community before demonstrating something that is incompatible with some of those beliefs is going to bear more fruit than this underhanded style.