Apparently there’s more than one way to earn a doctorate.
While institutions of higher education have been criticised for awarding honorary doctorates to non-graduates, it hasn’t stopped them from honouring accomplished musicians, artists, athletes, and actors for years.
Many celebrities on our list hold not one, but two or even three honorary doctorates from some of the most prestigious universities in the world.
Keep reading to find out which universities bestowed “Dr.” upon the likes of Kanye West, Magic Johnson, and Jon Bon Jovi.
Sean 'P. Diddy' Combs became Dr. Combs when he was honored with a Doctorate in Humanities during his commencement address at Howard University in 2014. Diddy enrolled in the university back in 1990 but dropped out shortly after to pursue a music career. Still, he said Howard University changed his life and he was humbled to receive a degree.
Baldwin earned a bachelor's in 1994 (he started his degree in 1979 but never finished) from NYU's Tisch School of the Arts and returned in 2010 to receive an honorary Doctorate of Fine Arts. The actor began a scholarship fund in 2010 called the Alec Baldwin Drama Scholarship Fund that helps students afford an NYU Tisch education.
The legendary film star was awarded an honorary Doctorate of Fine Arts from Bates College during his 2012 commencement speech.
Despite De Niro's controversial remarks about higher education -- he told students that he made a good decision and saved money by not attending college -- he left students with this wisdom: 'If you're an actor, always be true to your character ... If you're not an actor, have character and always be true to yourself.'
The incomparable Queen of Soul reportedly holds some 12 or more honorary degrees, including Doctorates of Music and Arts from Princeton and University of Pennsylvania. Most recently, Franklin graced the stage at Harvard's 2014 commencement to accept her honour and perform the national anthem.
In 2009, Parton was honored with a Doctorate of Humane and Musical Letters from University of Tennessee at Knoxville -- the second-ever honorary degree awarded by the school. Parton, a multi-Grammy award winner and member of the Country Music Hall of Fame said she felt proud to receive the honour from her home state.
New Jersey native and frontman of the eponymously named world-famous rock band, Jon Bon Jovi has two honorary doctorates: one from Monmouth University, awarded in 2001, and another from Rutgers University at Camden, awarded earlier this year for his leadership in civic justice and equality.
Late night talk-show host, former SNL writer, and Harvard graduate Conan O'Brien received an honorary doctorate from Dartmouth University in 2011. During the commencement speech he told students his 'first job as commencement speaker is to illustrate that life is not fair,' in ironic reference to his honour.
LL Cool J received an honorary degree from Northeastern University last year during his daughter's own graduation ceremony from the university. The rapper and actor, who never went to college himself, even got to present her with her diploma.
The artist and activist, who was married to the Beatles' John Lennon, most recently received an honorary doctorate at Pratt Institute's 125th commencement, which was held in 2014 at Radio City Music Hall. Ono also holds two more honorary doctorates from the University of Liverpool (which she supports in memory of her late husband) and Bard College.
The greatest heavyweight champion in history is more than just a boxer. Muhammad Ali is the recipient of two honorary Doctorates of Humanities from Princeton University and Muhlenberg College for his perseverance in and out of the ring. Ali has embarked on goodwill missions to Afghanistan and North Korea and been recognised with a lifetime achievement award from Amnesty International.
The comedian and satire news anchor's alma mater, Northwestern University, honored him with a Doctorate of Fine Arts in 2011.
On his show, 'The Colbert Report,' in 2006 he aired a sketch in which he jokingly made light of the 'Dr.' title he received from Knox College earlier that year.
Academy Award and Tony winner Denzel Washington delivered the commencement address at the University of Pennsylvania in 2011, where he also received an honorary doctorate.
'Do you have the guts to fail?' Washington asked students. 'If you don't fail, you're not even trying.'
'Tonight Show' host and former SNL cast member Jimmy Fallon attended the College of Saint Rose in the 1990s but left to purse a career in television before graduating. He returned in 2009 to present the school's commencement address and was honored with both his Bachelor's degree and an honorary doctorate for his television successes.
William Shatner gained a cult following for his repeated on-screen portrayal of Captain James T. Kirk in the 'Star Trek' series. His legendary status was recognised by his alma mater, McGill University, in 2011 when he received an honorary Doctorate of Letters.
The actor-producer was awarded an honorary doctorate from Howard University this year for his achievements in film.
Freeman also has an honorary Doctorate of Humane Letters from Boston University, which he received in 2013 during BU's 140th commencement.
Jack Nicholson, a three-time Academy Award winner and the most frequently Oscar-nominated male actor, was honored by Brown University in 2011 with an honorary Doctorate of Fine Arts. After high school, Nicholson went to the west coast with the intention of attending college and wound up working in Hollywood instead.
Accomplished actress Kerry Washington returned to her alma mater, George Washington University, in 2013 to receive an honorary doctorate. Washington, who was a presidential scholar for the arts at GW, also delivered the commencement speech.
'It's Always Sunny in Philadelphia' actor Charlie Day gave a hilarious commencement speech in 2014 at his alma mater, Merrimack College, and was also awarded an honorary Doctorate in Performing Arts.
He joked of his honour: 'Dr. Charlie Day sounds like some kind of club DJ ... And as a doctor I plan to start writing my own prescriptions immediately.'
In 2013, Bono turned down an honorary degree from NYU as not to overshadow his daughter's graduation from the university that same year.
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