The history of philosophy is the systematic study of the development of philosophical thought. It focuses on philosophy as rational inquiry based on argumentation, but some theorists also include myth, religious traditions, and proverbial lore.
Western philosophy originated with an inquiry into the fundamental nature of the cosmos in Ancient Greece. Subsequent philosophical developments covered a wide range of topics including the nature of reality and the mind, how people should act, and how to arrive at knowledge. The medieval period was focused more on theology. The Renaissance period saw a renewed interest in Ancient Greek philosophy and the emergence of humanism. The modern period was characterized by an increased focus on how philosophical and scientific knowledge is created. Its new ideas were used during the Enlightenment period to challenge traditional authorities. Influential developments in the 19th and 20th centuries included German idealism, pragmatism, positivism, formal logic, linguistic analysis, phenomenology, existentialism, and postmodernism.
Arabic–Persian philosophy was strongly influenced by Ancient Greek philosophers. It had its peak period during the Islamic Golden Age. One of its key topics was the relation between reason and revelation as two compatible ways of arriving at the truth. Avicenna developed a comprehensive philosophical system that synthesized Islamic faith and Greek philosophy. After the Islamic Golden Age, the influence of philosophical inquiry waned, partly due to Al-Ghazali's critique of philosophy. In the 17th century, Mulla Sadra developed a metaphysical system based on mysticism. Islamic modernism emerged in the 19th and 20th centuries as an attempt to reconcile traditional Islamic doctrines with modernity.
Indian philosophy is characterized by its combined interest in the nature of reality, the ways of arriving at knowledge, and the spiritual question of how to reach enlightenment. Its roots are in the religious scriptures known as the Vedas. Subsequent Indian philosophy is often divided into orthodox schools, which are closely associated with the teachings of the Vedas, and heterodox schools, like Buddhism and Jainism. Influential schools based on them include the Hindu schools of Advaita Vedanta and Navya-Nyāya as well as the Buddhist schools of Madhyamaka and Yogācāra. In the modern period, the exchange between Indian and Western thought led various Indian philosophers to develop comprehensive systems. They aimed to unite and harmonize diverse philosophical and religious schools of thought.
Central topics in Chinese philosophy were right social conduct, government, and self-cultivation. In early Chinese philosophy, Confucianism explored moral virtues and how they lead to harmony in society while Daoism focused on the relation between humans and nature. Later developments include the introduction and transformation of Buddhist teachings and the emergence of the schools of Xuanxue and Neo-Confucianism. The modern period in Chinese philosophy was characterized by its encounter with Western philosophy, specifically with Marxism. Other influential traditions in the history of philosophy were Japanese philosophy, Latin American philosophy, and African philosophy.