Friedrich may refer to:

Friedrich Wilhelm Nietzsche ( /ˈniːtʃə/;German pronunciation: [ˈfʁiːdʁɪç ˈvɪlhɛlm ˈniːtsʃə]; October 15, 1844 – August 25, 1900) was a German philosopher, poet, cultural critic and classical philologist. He wrote critical texts on religion, morality, contemporary culture, philosophy and science, displaying a fondness for metaphor, irony and aphorism.

Nietzsche's influence remains substantial within and beyond philosophy, notably in existentialism, nihilism and postmodernism. His style and radical questioning of the value and objectivity of truth have resulted in much commentary and interpretation, mostly in the continental tradition. His key ideas include the death of God, the Übermensch, the eternal recurrence, the Apollonian and Dionysian dichotomy, perspectivism and the will to power. Central to his philosophy is the idea of "life-affirmation", which involves an honest questioning of all doctrines that drain life's expansive energies, however socially prevalent and radical those views might be.

Caspar David Friedrich (September 5, 1774 – May 7, 1840) was a 19th-century German Romantic landscape painter, generally considered the most important German artist of his generation. He is best known for his mid-period allegorical landscapes which typically feature contemplative figures silhouetted against night skies, morning mists, barren trees or Gothic ruins. His primary interest as an artist was the contemplation of nature, and his often symbolic and anti-classical work seeks to convey a subjective, emotional response to the natural world. Friedrich's paintings characteristically set a human presence in diminished perspective amid expansive landscapes, reducing the figures to a scale that, according to the art historian Christopher John Murray, directs "the viewer's gaze towards their metaphysical dimension".

Friedrich was born in the Swedish Pomeranian town of Greifswald, where he began his studies in art as a youth. He studied in Copenhagen until 1798, before settling in Dresden. He came of age during a period when, across Europe, a growing disillusionment with materialistic society was giving rise to a new appreciation of spirituality. This shift in ideals was often expressed through a reevaluation of the natural world, as artists such as Friedrich, J.M.W. Turner (1775–1851) and John Constable (1776–1837) sought to depict nature as a "divine creation, to be set against the artifice of human civilization".

Friedrich August Hayek CH (German pronunciation: [ˈfʁiːdʁɪç ˈaʊ̯ɡʊst ˈhaɪ̯ɛk]; 8 May 1899 – 23 March 1992), born in Austria-Hungary as Friedrich August von Hayek, was an economist and philosopher best known for his defense of classical liberalism. In 1974, Hayek shared the Nobel Memorial Prize in Economic Sciences (with his political rival, Gunnar Myrdal) for his "pioneering work in the theory of money and economic fluctuations and... penetrating analysis of the interdependence of economic, social and institutional phenomena." He considered the efficient allocation of capital to be the most important factor leading to sustainable and optimal GDP growth, and warned of harms from monetary authority manipulation of interest rates. Interest rates should be set naturally by equilibrium between consumption of goods or capital stock.

Hayek is considered to be a major economist and political philosopher of the twentieth century. Along with his mentor Ludwig von Mises, he was an important contributor to the Austrian school of economic thought. Hayek's account of how changing prices communicate information which enable individuals to coordinate their plans is widely regarded as an important achievement in economics. He also contributed to the fields of systems thinking, jurisprudence, neuroscience and the history of ideas.