From the Amy Wallace story:
The rejection of hard-won knowledge is by no means a new phenomenon. In 1905, French mathematician and scientist Henri Poincaré said that the willingness to embrace pseudo-science flourished because people “know how cruel the truth often is, and we wonder whether illusion is not more consoling.” Decades later, the astronomer Carl Sagan reached a similar conclusion: Science loses ground to pseudo-science because the latter seems to offer more comfort. “A great many of these belief systems address real human needs that are not being met by our society,” Sagan wrote of certain Americans’ embrace of reincarnation, channeling, and extraterrestrials. “There are unsatisfied medical needs, spiritual needs, and needs for communion with the rest of the human community.”
Looking back over human history, rationality has been the anomaly. Being rational takes work, education, and a sober determination to avoid making hasty inferences, even when they appear to make perfect sense. Much like infectious diseases themselves — beaten back by decades of effort to vaccinate the populace — the irrational lingers just below the surface, waiting for us to let down our guard.
UPDATE: FactCheck.org article: "Inoculation Misinformation - Claims that the "swine flu" vaccine is dangerous range from seriously overblown to flat-out false."