A common theme on this blog is irritation with the scientific illiteracy of much of the public. This is, it needs to be noted, different from a lack of educational achievement. While it is popular to divide the world into uneducated cretins and enlightened college graduates, this is complete bullshit. While certain forms of anti-scientific thinking are popular among those without degrees, things such as vaccine denial, hysteria over GMOs, and belief in bogus "energy healing" are extremely common among people with degrees.
In fact, my own experience is that those with degrees tend to be far more intractable in their false beliefs in large part because they have degrees. I have lost count of the number of times that I have had a conversation with someone who was spouting pseudo-scientific nonsense and had them respond finally with "well, I earned a degree from Stanford [or another major university], so clearly I'm smart enough to understand this!"
A degree from Stanford, or anywhere else, in literature or history does not make one knowledgeable about biology, medicine, or physics. Certainly, someone with such a degree can become knowledgeable about these subjects, but to rely on the fact that you have a degree and not on training on the subject in question is a sign of sloppy thinking.
Most of the time, people are simply accepting whatever is convenient for their social and political views, and ignoring any disconfirming data. So, people on the political right are perfectly willing to accept marginal and poorly done studies that conclude that there is doubt about climate change contrary to the general scientific consensus, but people on the political left are willing to accept equally dubious studies that allege harm from GMO crops; people on the social right are willing to buy all manner of nonsense about the alleged harms that homosexuals do to their families, but people on the social left are only too ready to accept dubious studies concerning the role of self esteem in crime.
Part of the problem is, I think, that there is a tendency to equate scientific literacy with acceptance of certain conclusions, a scientifically literate person is one who accepts that evolution occurred, to use one example. In truth, scientific literacy is about having a knowledge of the methods of science. Importantly, it is about knowing the parameters under which scientific knowledge is generated.
Let's take the example of the study by Andrew Wakefield that is used to make claims about a link between vaccines and autism. Many people either accepted it because it gelled with their social and political views (medicine bad, big pharma evil) or rejected it because it clashed with their views (vaccines are part of the progress of mankind!). Very few people who hold a strong view on it have actually read it.
I did read it. When I read it, I, like everyone else, was unaware that Wakefield had falsified data or tweaked his results. But I was struck by two things: 1) the causal mechanism that he suggested, wherein the thimerisol in the vaccine caused inflamation int he digestive tract that allowed infection leading to autism, didn't sound plausible. However, I am not a medical doctor and am aware that there may be something to this that I simply didn't understand (this recognizing of one's own limits in knowledge is an important part of scientific literacy). 2) The sample size was small, totaling 12 children. A small sample size is useful in trying to prove the plausibility of a basic concept, but is insufficient for actually proving anything medical because of the high odds of random chance interfering with a sample size that small.
So, after reading it, I went away thinking that it sounded implausible, but that I didn't know enough about the subject to judge that too strongly, and that the sample size was small and larger scale studies would be needed to find a link between vaccines and autism with any confidence. In other words, my own scientific literacy pointed to the problems with the study, but prevented me from ignoring it outright until such time as further data was generated. I continued to get vaccinations myself, and encouraged people with children to get them, as the general scientific consensus was still in favor of them, but I was open to the possibility that this might be wrong.
In time, large scale studies were performed, and they showed that there is no link between vaccines and autism, and Wakefield has since been revealed as an outright fraud. However, by that time, numerous people had jumped on the bandwagon of a hypothesis supported by a dubious small-scale study, leading to the resurgence of numerous nearly eradicated (and in some cases deadly) illnesses. A greater degree of scientific literacy would have cautioned people early on, and they would have considered the possibility of the study being accurate alongside the need for further study to test the hypothesis. Considering that children have been injured and killed because of vaccine denial, this is a case where a lack of scientific literacy resulted in very serious consequences.
Recently, studies have been published arguing that organic farming leads to healthier soil and that acupuncture is effective in dealing with pain. In both cases, people either jumped on board or rejected the claims based on their pre-existing beliefs, without ever actually looking into the contents of the studies themselves. The acupuncture study was riddled with problems (for a summary of it and similar studies, look here) that effectively eliminate it from consideration, while the organic farm studies are interesting and seem plausible, but tend to have small sample sizes and some methodological problems that decrease their ability to elucidate the issue. However, you would only know these things if you read the papers themselves and read the scientific discussions and criticisms of the papers, which most people don't. Most people go to Fox News or the Huffington Post and accept the summary from whichever source aligns with their social and political views without ever questioning the actual science itself. And, importantly, this is extremely common amongst educated people with degrees from well-respected universities.
Acceptance and rejection of many scientific claims often falls along political lines. Left-leaning individuals are more likely to accept that acupuncture is great, that organic farming improves soil, and that vaccines cause autism, all without seriously considering problems with and criticisms of the research; right-leaning individuals are more likely to embrace climate change denial and notions like intelligent design. Those with college degrees are most likely to be able to convince themselves that they are too smart to have been fooled and to be able to rationalize their conclusions, no matter whether they are debatable but possible (organic farming improves soil) or flat-out false (intelligent design). All are scientifically illiterate, and yet all think that they alone understand the world.
In sum: scientific literacy isn't about having the right knowledge, it's about having an understanding of how science works, which means knowing that one study doesn't "prove" anything, that multiple studies are necessary, the larger the scale the better, and that the criticisms of the studies are important - having certain base knowledge (the Earth orbits the sun, DNA codes many of our traits, etc.) is necessary and important but is no literacy in of itself. It's about knowing that you are not knowledgeable about any but a narrow range of topics, and that you have to accept that you may be wrong and that people ideologically opposed to you may be right on any given topic. It's about knowing that your educational background prepares you to evaluate information and ideas within the field that you studied, and does not make you more likely to be able to evaluate information outside of that field. And, importantly, being scientifically literate means understanding that the things that you wish to be true or that align with your beliefs may be false, and that you have to listen to criticism of ideas that you hold dear, for those criticisms might be correct.