Simplify the following text for a Grade 7 native English-speaking person.
Original: He published Les Mots et les choses ( The Order of Things ) during the height of interest in structuralism in 1966 , and Foucault was quickly grouped with scholars such as Jacques Lacan , Claude LÃ vi-Strauss , and Roland Barthes as the newest , latest wave of thinkers set to topple the existentialism popularized by Jean-Paul Sartre .
Simplified: In 1966 he published Les Mots et les choses ( The Order of Things ) , which was very popular .