A psychological profile of Lady Macbeth would probably say things like "manipulative," "paranoid," "unlikely to create genuine social bonds," and "a bit of a germaphobe." An analysis of Benedick from Much Ado About Nothing would likely produce words like "cocky," "arrogant," and "highly social." But how about an analysis of Shakespeare himself? In a study published in Psychological Science, Ryan Boyd and James Pennebaker at the University of Texas at Austin used a combination of text-analyzing software and psychological theory to create a unique profile of the Bard that links him to the play Double Falsehood.

Scholars have long debated its origins: Some argue that Shakespeare was fully responsible, while others believe that Lewis Theobald, whose name was attached to the play when it was first published in 1728, was the author—in 1727, Theobald claimed that he had three copies of Shakespeare's lost play, Cardenio, and planned to adapt it into Double Falsehood

In order to put an end to the debate, Boyd and Pennebaker used software to identify and evaluate certain features present in the works of Shakespeare, his occasional collaborator John Fletcher, and Theobald. As Science Daily explains,

the researchers' software examined the playwrights' use of function words (e.g., pronouns, articles, prepositions) and words belonging to various content categories (e.g., emotions, family, sensory perception, religion). They had the software identify themes present in each of the works to generate an overarching thematic signature for each author.

Boyd and Pennebaker also rated how "categorical" the writing was in order to understand each author's thought process and to give each of them an accurate "psychological signature." 

Categorical writing tends to be heavy on nouns, articles, and prepositions, and it indicates an analytic or formal way of thinking. Research has shown that people who rate high on categorical thinking tend to be emotionally distant, applying problem-solving approaches to everyday situations. People who rate low on categorical thinking, on the other hand, tend to live in the moment and are more focused on social matters.

From analyzing Double Falsehood—along with 33 plays by Shakespeare, nine by Fletcher, and 12 by Theobald—the researchers concluded that the style of the play in question most closely resembles that of a "sociable and fairly well educated," individual or the exact opposite of Theobald, who Boyd describes as "very smart but probably somewhat of a jerk." Pennebaker notes that while Shakespeare was the clear author for the first three acts, there's more evidence of Fletcher's involvement in four and five. 

Another case closed.