Jimmy Carter's IQ Might Surprise You

In 2006, the academic journal Political Psychology published a study by Dean Keith Simonton, titled: "Presidential IQ, Openness, Intellectual Brilliance, and Leadership: Estimates and Correlations for 42 U.S. Chief Executives." (via the University of Buffalo). Simonton's work presented estimated IQ profiles for each of the 42 presidents up to the then-current President George W. Bush. As Simonton notes, the IQ test was a 20th-century invention, but he explained his methodology for earlier presidents thus:

"Assessment began by extracting personality descriptions from several biographical sources for 39 presidents from Washington through Reagan. All identifying information was then removed to produce anonymous biographical profiles." Simonton explains that these profiles were then analyzed by a group of judges for positive descriptors that might give an indication of their intelligence, creativity, and ability: "These latter measures were then subjected to a factor analysis that obtained 14 distinct dimensions. One of these factors included such items as 'intelligent,' 'wise,' 'inventive,' 'interests wide,' 'artistic,' 'curious,' 'sophisticated,' 'complicated,' and 'insightful' (but not 'dull' or 'commonplace')."

Using this methodology, Simonton was able to share some intriguing findings, including about George W. Bush, who had recently been the subject of a hoax email claiming that an IQ test had exposed him as the least intelligent president of all time (via Snopes). Simonton's study gave Bush's IQ as significantly higher than that in the earlier hoax email — but came to the same conclusion regarding Bush's place in the league table of presidential intelligence.

Conversely, Simonton also gave a surprisingly high rating to one of the U.S.'s most unassuming leaders: Jimmy Carter.

As noted by Reader's Digest, Jimmy Carter rose from a humble American background in Georgia to become one of the best-loved presidents of the 20th century. His career was distinguished by his gift for diplomacy, including his work on establishing a diplomatic relationship with China and his push to broker a nuclear limitation deal with Russia, according to the White House. Carter continued his advocacy of peaceful causes in the years following his departure from the White House in 1981 and was awarded the Nobel Peace Prize in 2002.

Carter was arguably aided in these causes by his humble and likable character, but as Dean Keith Simonton's study reveals, his personality has masked a formidable intellect (via the University of Buffalo). Simonton postulates that Carter has an IQ of 156.8, making him one of the most intelligent presidents in American history, beating the likes of Teddy Roosevelt and Woodrow Wilson, but a hair behind Bill Clinton, whose IQ is believed to be 159.

And the highest presidential IQ? 175, the score given to John Quincy Adams.