Denialism, Wikipedia defines it as human behavior where individuals choose to deny reality as a way to deal with an uncomfortable truth. Science is the ever-growing body of knowledge which seeks to test and measure reality in the—thus far conceived—best possible way, the scientific method. It operates with emotionless impunity, stripping away bias and unrepeatable findings, until the best possible theory to explain observed natural phenomenon is reached by peer-review and consensus. Sometimes science gets corrupted by bias, capitalism, or any number of factors, and we can point to certain instances in history or current events where this is so (take tobacco safety for instance). Even with error, the method razors through, who do you think discovered the harm tobacco actually does, in the end? It certainly wasn't the science denialists or the alt-med quacks. It was the persistence, in the face of substantial corporate pressure, of scientists studying the effects of cigarettes on health and loudly protesting the consensus until it changed.
In Michael Specter's book, Denialism, he takes on several strains of anti-science thinking. Fear of science and critical thinking, the anti-vaccination movement, organic food myths and anti-GMO activism, nutritional supplements and homeopathy cures, and genetics in regards to racial ethnicity. Each topic is well argued with plenty of entertaining interviews, quips, and Specter's personal insights. I could write a lengthy article in agreement with each of these topics, but Specter covers each point quite well already in his book, which I of course highly recommend. This is a strong first book for a writer who's future work I highly anticipate.