Sowell introduces us to his concept of competing visions in American political life. The constrained vision sees progress limited by human nature. Whatever solutions humans develop to restrain or ameliorate human evils will themselves impose costs or create new social ills. Thus, public policy must always deal in trade-offs rather than absolutes. The unconstrained vision believes human moral improvement has no fixed limits, thus all human problems are entirely solvable. These two visions find themselves talking past one another in the political sphere.