In this article, Bradley Watson shows how Oliver Wendell Holmes, Jr., one of the most-cited and influential U.S. Supreme Court justices, formulated a strong critique of natural law and set the stage for modern attitudes towards jurisprudence. According to Holmes, there are no objective standards of morality upon which to base laws, and thus law must be concerned only with practical effects and social advantage. In holding this view, Holmes was influenced by the doctrines of pragmatism and Social Darwinism, which asserted that life is constantly adapting to its environment, and that change or progress is the only and ultimate end of history. For Holmes, law is merely the prediction of what the courts will do. Since there are no standards of morality, judges cannot decide cases by reason, but rather must do so by sentiments or “felt necessities.” As such, what is true is what gets accepted in the marketplace of ideas, and what is right is simply what triumphs. Although Holmes respected certain judicial rulings as expressions of the popular will, he also argued that judges needed to be active in interpreting the law according to their own feelings. Both judicial activism and judicial restraint are therefore needed for the sake of progress. This view of the judge’s role continues to exert great influence on contemporary legal philosophy.