Sheldon is a theoretical physicist at Caltech, who shares an apartment with his best friend and colleague Leonard Hofstadter. Sheldon does exhibit a strict adherence to routine, with a complete lack of social skills, and a poor understanding of irony, sarcasm and humor, plus a general lack of humility and empathy. He is a member of their own superior intellect than those who reside around him. Sheldon's critics and fans have speculated that his personality is consistent with a diagnosis of Asperger syndrome and/or obsessive compulsive disorder.
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