By Patrick Appel
Jonah Lehrer is amused by the myth of the rational voter:
The problem, as political scientist Larry Bartels notes, is that people aren't rational: we're rationalizers. Our brain prefers a certain candidate or party for a really complicated set of subterranean reasons and then, after the preference has been unconsciously established, we invent rational sounding reasons to justify our preferences. This is why the average voter is such a partisan hack and rarely bothers to revise their political preferences. For instance, an analysis of five hundred voters with "strong party allegiances" during the 1976 campaign found that, during the heated last two months of the contest, only sixteen people were persuaded to vote for the other party. Another study tracked voters from 1965 to 1982, tracing the flux of party affiliation over time. Although it was an extremely tumultuous era in American politics - there was the Vietnam War, stagflation, the fall of Richard Nixon, oil shortages, and Jimmy Carter - nearly 90 percent of people who identified themselves as Republicans in 1965 ended up voting for Ronald Reagan in 1980.
That said, when our preferences in the voting booth can be influenced they are often influenced by completely arbitrary factors. (In a 2004 paper, Bartels argued that "2.8 million people voted against Al Gore in 2000 because their states were too dry or too wet" as a consequence of that year's weather patterns. In other words, these climatic acts of god cost Gore the election.)