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Silly Creatures is the collective name Uncle Traveling Matt gives to human beings in Fraggle Rock. This title encompasses Doc, as well as the many people encountered during Matt's travels. The habits of the Silly Creatures fascinate yet often perplex Matt. The Silly Creatures have been known to react negatively to Matt's scientific observations. Matt generally invents his own names to describe the customs and habits of Silly Creatures, or utilizes terms relevant to Fraggle Rock, describing construction workers as "Doozers" or Trick or Treaters as ugly, but not as ugly as Gorgs.

Though the Silly Creatures are mostly anonymous, a few have been played by Fraggle Rock crew in cameos:

• Dave Goelz as the rollercoaster passenger in Episode 105: The Thirty-Minute Work Week
• Phil Balsam as the street musician in Episode 218: The Day the Music Died