A blood-pressure theory became a superhero’s weapon
In the 1920s, psychologist William Moulton Marston helped develop an early form of the lie detector based on a simple idea: a person trying to deceive might become emotionally stirred, and that reaction could raise blood pressure. The test tracked systolic pressure—the force of blood against artery walls as the heart contracts—as an examiner asked questions.
That was not the same as reading a lie directly. The instrument registered a bodily response; interpreting that response as deception was the crucial leap. Marston nevertheless believed blood pressure could offer a window into whether someone was telling the truth.
From laboratory instrument to golden lasso
Years later, Marston brought that conviction into Wonder Woman, the comic-book heroine he helped create. Her golden lasso did what his instrument could only claim to do: anyone caught in it had to tell the truth. The idea turned an abstract psychological theory into a power readers could see at work, with the lasso serving as both restraint and truth detector.
The connection was especially fitting for a character shaped by Marston’s interest in bondage and submission. In the comics, being bound by the lasso could mean losing the ability to conceal the truth—but it also made truth-telling part of Wonder Woman’s action, not just a lesson delivered in dialogue.
The promise—and the limit—of the idea
Marston’s two creations reveal the same ambition in different forms: to make hidden feelings legible. A blood-pressure device tried to infer an inner state from the body; Wonder Woman’s lasso made that inference infallible by turning it into fantasy. The machine measured a reaction, while the comic supplied certainty. That gap is what makes the golden lasso such a memorable transformation of an early lie-detection theory.
