The article delves into the philosophical discourse on human nature as addressed by American thinker Thomas Sowell. He categorizes thinkers into two primary types based on their views of human potential: those with an unrestricted perspective and those with a restricted perspective. Proponents of the unrestricted view, including figures like Rousseau and Marx, believe in human beings' capacity for self-reform through free will and rationality. In contrast, advocates of the restricted perspective, such as Augustine and Freud, argue that humans have inherent limitations that prevent significant self-reform.