Nancy Campbell Cartwright (born October 25, 1957) is an American voice actress. She is perhaps best known for providing the voices of Bart Simpson, Nelson Muntz, Todd Flanders and Ralph Wiggum on the animated television show The Simpsons. Stated in interview on Inside the Actors Studio

Nancy Cartwright (born 1943) is a professor of philosophy at the London School of Economics and the University of California at San Diego. Cartwright is the president-elect of the Western Division of the American Philosophical Association.

Her PhD in philosophy was earned at the University of Illinois at Chicago under the direction of Brian Skyrms. She previously taught at Stanford University and was married to the philosopher Stuart Hampshire, now deceased. She was also previously married to Ian Hacking. Her research interests include the history and philosophy of science, especially economics and physics, and causal inference and objectivity in science. She has also written on the history of logical positivism. Her approach to the philosophy of science is associated with the so-called "Stanford school" of John Dupré, Peter Galison, and Ian Hacking.

Children, with Warren Murphy, Lucy Mae and Jackson.

When she auditioned for "Simpsons, The" (1989), she was rehearsing for the voice of "Lisa Simpson", not "Bart Simpson". During final preparations while reading the script, she realized she could do "Bart Simpson"'s voice.

Was friends with Daws Butler, the voice of Yogi Bear, Huckleberry Hound and hundreds of others. They regularly exchanged letters, and soon he was addressing her "Dear Pixie." He sent her scripts to record, and then critiqued the tapes she returned. At 12, she joined a children's theatre company and made her first stage debut in "An Old-Fashioned Christmas". The director asked her to join his summer theatre group. She traveled with them for four years. As a senior, she was president of the Forensic League at Fairmont West High school.

Like many tourists, Cartwright attempted to disturb the notoriously unflappable guards at Buckingham Palace in London. When she blurted, "I'm Bart Simpson, who the hell are you?", she succeeded.

Ironically her character Ethel in Twilight Zone: The Movie (1983) - years before her role as Bart Simpson - is "wished" into a television set where she is chased around and then eaten alive by a cartoon monster.

The segment of Twilight Zone: The Movie (1983) in which she appears is based on the same episode that was later parodied in a "Simpsons" Halloween special.

Her character, Bart Simpson, was rated number 2 in Comedy Central's newest show 'Mouthing Off: 51 Greatest Smartasses'.

Attended Ohio University from 1976-1978 as an interpersonal communication major and was awarded the Cutler Scholarship for academic excellence and leadership.

Appointed Honorary Mayor of Northridge, California, USA (2005)

Was offered the chance to do the female voices for "South Park" (1997), but turned it down because she felt the show was too offensive.

She met the future Supervising Director of "Simpsons, The" (1989), David Silverman (I), when they were both students in UCLA's Art Department in the late 1970s. They jokingly made an agreement they would one day work on a show together, but didn't find out their deal came through until they saw the credits of the first episode of the series.