Final answer:
The fictional city that uses the motto "A noble spirit embiggens the smallest man" is Springfield from the TV show The Simpsons.
Step-by-step explanation:
The fictional city's motto, "A noble spirit embiggens the smallest man," is from the fictional city of Springfield, best known as the setting of the animated television series The Simpsons. This phrase reflects the idea that one's character and dignity can elevate their standing regardless of their physical size or social status. It exemplifies the show's use of humor and satire to comment on various aspects of society, culture, and human nature.