Simplify the following text for a Grade 9 native English-speaking person.
Original: Frederic Myers may be regarded as an `` important early depth psychologist '' , and his significant influence on colleagues like William James , Pierre Janet , and ThÃ odore Flournoy and also Carl G. Jung has been well documented .
Simplified: Frederic Myers had a big influence on colleagues like William James , Pierre Janet , and ThÃ odore Flournoy and also Carl Jung .