Twenty-seven percent of American voters claim they choose presidential candidates primarily on the basis of the nominee's character and moral values, according to a poll conducted after the 2000 elections. However, candidates with a solid character--straightforward, dutiful and disciplined--often run into trouble being an effective president, says Steven J. Rubenzer, PhD, a Houston-based clinical psychologist and co-founder of the Foundation for the Study of Personality in History. In fact, a tendency to tell the truth can actually harm a president's shot at being considered historically "great," he says.

"We don't hear too many candidates touting that they are a better liar than the others," says Rubenzer. "But it seems to increase their chances of putting their policies in place."

For example, the president widely considered the greatest of the 19th century, Abraham Lincoln, skillfully "massaged" the truth and cleverly shifted positions, when necessary, despite his "Honest Abe" reputation, said Rubenzer. For example, he softened his opposition to slavery in an attempt to keep the country unified.

But skillful prevarication isn't the only ingredient necessary for a successful presidency, says Rubenzer. Chief executives also profit from high intelligence and "achievement-striving"--a preference for setting and tackling high goals, says the psychologist.

Rubenzer and his colleagues, including psychologist Deniz Ones, PhD, at the University of Minnesota, came to this conclusion by assessing each past American president's straightforwardness, intelligence, achievement-striving and other personality factors. They did so by asking about four experts and biographers for each president to score them using the NEO personality inventory--a commonly used personality test. Though the NEO does not assess intelligence directly, the personality measure "openness to experience" correlates highly with ratings of cognitive ability, says Rubenzer.

The psychologists then linked the chief executives' personality scores with success in office, as rated by the Murray-Blessing survey of 846 academic historians, which was published in the book "Greatness in the White House: Rating the Presidents, Washington through Carter," (Pennsylvania State University Press, 1988).

Those presidents who received high marks from historians tended to be smart, have ambitious goals and be willing to bend the truth, according to results published in Rubenzer's new book--co-authored with retired clinical psychologist Tom Faschingbauer, PhD--"Personality, Character & Leadership in the White House: Psychologists Assess the Presidents" (Brassey's, 2004). And these findings converge with previous research by political psychologists such as Dean Simonton, PhD, at the University of California, Davis, who finds that intelligence, as measured by a combination of personal achievements, analysis of a president's interests and scores on the personality measure openness to experience, predicts presidential success above all other individual factors.

Knowing what personalities make a good fit for the White House could help psychologists and historians understand a former president's weaknesses, says Rubenzer, and even predict how a candidate for the presidency might fare once in office.

Intellect's importance

Most presidents are not keen on publicizing their IQ scores, and so this variable, like all chief executives' personality and cognitive factors, must be measured at a distance, says Rubenzer. While other researchers have estimated the intelligence of presidents by analyzing their writings or accomplishments, Rubenzer and his colleagues used items from the NEO measure of openness to experience.

"Openness overlaps with intelligence because to some degree you have to be intelligent to appreciate new experiences," explains Simonton. "People who are low in intelligence, their systems are overwhelmed by the very rich environments that are attractive to people who are open to new experiences." There are, of course, certainly exceptions, he notes.

Presidents such as Lincoln and Thomas Jefferson--also widely considered successful chief executives by historians--tended to score high on openness and therefore intelligence, Rubenzer found.

"We weren't surprised--intelligence is a well established predictor of performance in all kinds of jobs," he says.

An as-yet unpublished study by Simonton confirms this hypothesis. Simonton combined three previous studies' data on presidential intelligence scores, including Rubenzer's openness scores. He then linked composite scores with presidential success, as measured by 12 surveys of historians and polls of the American population.

The researcher found that differences in intelligence accounted for about 10 percent of the variance in presidential greatness--making intelligence about as good a predictor for a president's success as the SAT is at predicting a student's first-semester college grades.

"Intelligence isn't the only factor that contributes to a president's success--the political climate and other situational factors certainly matter too," says Simonton. "But intelligence seems to be an across-the-board advantage."

However, the personality factors that increase candidates' chances for success in office are not necessarily the same as those that help them get elected, psychologists say. For example, intellectual brilliance seems negatively related to a president's margin of victory, finds Simonton.

"The ones who are the most intellectually brilliant are often barely elected," he says. "They have trouble speaking in sound bites and communicating with the public."

For example, Woodrow Wilson, a president historians rated as intelligent and the only American president with a PhD, won with only two-fifths of the popular vote, Simonton notes.

Ambition's double-edge

While intelligence can make for a good president but a bad candidate, achievement-striving--or the tendency to work toward lofty goals--may benefit presidents both on the campaign trail and while in office.

"Achievement-striving means people have high goals, but more importantly, they work hard to achieve them," says Rubenzer. "They stay focused; they are kind of workaholics."

Successful presidents such as Lincoln and Theodore Roosevelt outscore 90 percent of Americans on this personality factor, found the psychologist--perhaps not surprisingly since becoming president is itself an accomplishment, says Rubenzer.

In contrast, research by psychologist David Winter, PhD, at the University of Michigan, finds that achievement motivation, defined as a drive to do things well, may be a hindrance for presidents in office.

In a study published in a chapter of "Political Leadership for the New Century" (Praeger, 2002), Winter and his colleagues rated the achievement motivation of presidents by counting the number of achievement-related phrases in presidents' inaugural addresses, including references to excellence and future goals. Presidents such as Woodrow Wilson and Jimmy Carter, who scored high on achievement imagery, tended to meet resistance while attempting to implement their policies.

"People high in achievement motivation do best when they have large amounts of personal control," says Winter. "They become frustrated by the bureaucracy of politics."

Indeed, in Rubenzer's personality analysis Carter, who historians note as stymied by the checks and balances of the presidency, scored very high on achievement-striving--in the top 1 percent of all former presidents. However, Carter had two fatal personality flaws: a lack of assertiveness and a tendency to be straightforward, notes the psychologist.

"A president has to influence, either by deceit or forcefulness," says Rubenzer. "When you see those two scores on someone who is otherwise so qualified you think, well, maybe that is the reason."

This observation is similar to Winter's analysis of Carter through his inaugural address, which found him low in power motivation--another predictor of presidential success, he says.

With these lessons in mind, those 37 percent of voters who cast their ballots for the presidency based primarily on issues may want to weigh in the candidates' character after all--given that the person who seems smart, ambitious and assertive, but not necessarily candid, may be the man or woman best suited for the job.

Further Reading

  • Rubenzer, S.J., & Faschingbauer, T.R. (2004). Personality, character & leadership in the White House: Psychologists assess the presidents. Washington, DC: Brassey's.

  • Simonton, D.K. (2002). Intelligence and presidential greatness: Equation replication using updated IQ estimates. In S.P. Shohov (Ed.), Advances in psychology research (pp. 143-153). Hauppauge, NY: Nova Science Publishers.

  • Winter, D.G. (2002). Motivation and political leadership. In L. Valenty & O. Feldman (Eds.), Political leadership for the new century: Personality and behavior among American leaders (pp. 25-47). Westport, CT: Praeger.