What will it take for George W. Bush or Al Gore to become a great president? If they take a lesson from their forebears, the first step to greatness in the Oval Office is an open mind and a taciturn manner, according to a study presented at APA's 2000 Annual Convention.

The research, which examined personality traits of all U.S. presidents, found that the most successful presidents tend to be hard-working and achievement-minded, be willing and able to speak up for their interests and value the emotional side of life.

"They tend to trust in the traditional sources of moral authority, yet are willing to bend the truth and to bully or manipulate people to get their way," said psychologist Steven J. Rubenzer, PhD, of Houston, who conducted the study with Thomas Faschingbauer, PhD, of Richmond, Texas, and Deniz S. Ones, PhD, of the University of Minnesota, as part of the Personality and the President Project.

To determine the personality traits of each American president, the researchers analyzed questionnaires on individual presidents, which were completed by more than 100 historical experts. The historians rated presidents on their character for the five years before they became president. (The researchers did not take into account a president's behavior while in office because the pressure of the presidency might change his behavior.)

Rubenzer and his colleagues measured each president's psychological characteristics by using the Revised NEO Personality Inventory. Then they correlated these psychological characteristics with the degree of a president's greatness, determined by referencing generally accepted lists of America's greatest presidents. In order, Abraham Lincoln, Franklin Delano Roosevelt, George Washington, Thomas Jefferson, Theodore Roosevelt, Woodrow Wilson, Harry Truman, Andrew Jackson, Dwight D. Eisenhower and James Madison ranked as the 10 greatest U.S. presidents.

Openness to experience produced the highest correlation between personality and greatness. The researchers hypothesize that openness and presidential greatness correlate at least partially because individuals with higher cognitive abilities may have more open minds. Unfortunately, even though cognitive ability may be one of the best predictors of presidential success, there is no direct measure of cognitive ability for all presidents to statistically test the idea.

In addition to open-mindedness, great presidents were rated as attentive to their emotions, willing to question traditional values and try new ways of doing things, imaginative and more interested in art and beauty than less successful presidents. They tend to be stubborn and ready to fight if picked on, the study said.

Most presidents are clearly extroverts, the study found, although earlier presidents were less so than those who have served since the rise of the media. Some facets of extroversion correlated moderately with presidential greatness; the single most powerful indicator was assertiveness.

"Presidents who succeed set ambitious goals for themselves and move heaven and earth to meet them," the authors noted.

The study also revealed a slight correlation between a president's disagreeableness and greatness. Interestingly, "tender-mindedness," or concern for the less fortunate, had a moderately large correlation with attaining historical greatness. The researchers also found that being a bit disorganized, as Lincoln was, is somewhat of an asset for attaining historical greatness.