Simplify the following text for a Grade 8 native English-speaking person.
Original: He was influenced by the utopian communist theories of FranÃ ois-No Ã `` l Babeuf and Claude Henri de Saint-Simon .
Simplified: The ideas of FranÃ ois-No Ã `` l Babeuf and Claude Henri de Saint-Simon had an important influence on his work .