This quote is about social constructs and the idea that they are made up by people. The complete quote is:

“The first person who, having fenced off a plot of land, thought of saying ‘This is mine’ and found people simple enough to believe him was the real founder of civil society.”

Jean-Jacques Rousseau wrote this in 1755 in his essay “Discourse on the Origin and Basis of Inequality Among Men.” In it, he challenged traditional notions of society and politics, arguing that social inequality arises from human convention rather than natural law. 

In chapter 10 of “30 Philosophers,” this quote serves as a catalyst for exploring skepticism and the distinction between nature and human-made social constructs. By recognizing that many societal norms are based on collective agreement rather than objective truth, we can begin to challenge and redefine them. This skepticism is essential for fostering critical thinking, promoting social change and striving towards a more equitable society.