Philosophy in the context of Quantum information

Classical Athens, known contemporaneously simply as Athens (Ancient Greek: Ἀθῆναι, Athênai [atʰɛ̂ːnai̯]; Modern Greek: Αθήναι, Athine [aˈθine]), was the major urban centre of the notable polis (city-state) of the same name during the classical period (480–323 BC) of ancient Greece, located in Attica, Greece, leading the Delian League in the Peloponnesian War against Sparta and the Peloponnesian League. Athenian democracy was established in 508 BC under Cleisthenes following the tyranny of Isagoras. This system remained remarkably stable, and with a few brief interruptions, it remained in place for 180 years, until 322 BC (amid the aftermath of the Lamian War). The peak of Athenian hegemony was achieved during the Age of Pericles in the 440s and 430s BC.

In the classical period, Athens was a centre for the arts, learning, and philosophy, and it was the home of Plato's Academy and Aristotle's Lyceum. Athens was also the birthplace of Socrates, Plato, Pericles, Aristophanes, Sophocles, and many other prominent philosophers, writers, and politicians of the ancient world. It is widely referred to as the cradle of Western civilization and as the birthplace of democracy, largely due to the impact of its cultural and political achievements during the 5th and 4th centuries BC on the rest of the then-known European continent.

Ancient Greek philosophy arose in the 6th century BC. Philosophy was used to make sense of the world using reason. It dealt with a wide variety of subjects, including astronomy, epistemology, mathematics, political philosophy, ethics, metaphysics, ontology, logic, biology, rhetoric and aesthetics. Greek philosophy continued throughout the Hellenistic period and later evolved into Roman philosophy.

Greek philosophy has influenced much of Western culture since its inception, and can be found in many aspects of public education. Alfred North Whitehead once claimed: "The safest general characterization of the European philosophical tradition is that it consists of a series of footnotes to Plato". Clear, unbroken lines of influence lead from ancient Greek and Hellenistic philosophers to Roman philosophy, early Islamic philosophy, medieval scholasticism, the European Renaissance and the Age of Enlightenment.

Western philosophy refers to the philosophical thought, traditions, and works of the Western world. Historically, the term refers to the philosophical thinking of Western culture, beginning with the ancient Greek philosophy of the pre-Socratics. The word philosophy itself originated from the Ancient Greek φιλοσοφία (philosophía), literally, 'the love of wisdom', from Ancient Greek: φιλεῖν (phileîn), 'to love', and σοφία (sophía), 'wisdom'.

Western philosophy stands in contrast to other cultural and regional traditions like Eastern philosophy.

Cosmology (from Ancient Greek κόσμος (cosmos) 'the universe, the world' and λογία (logia) 'study of') is a branch of physics and metaphysics dealing with the nature of the universe, the cosmos. The term cosmology was first used in English in 1656 in Thomas Blount's Glossographia, with the meaning of "a speaking of the world". In 1731, German philosopher Christian Wolff used the term cosmology in Latin (cosmologia) to denote a branch of metaphysics that deals with the general nature of the physical world. Religious or mythological cosmology is a body of beliefs based on mythological, religious, and esoteric literature and traditions of creation myths and eschatology. In the science of astronomy, cosmology is concerned with the study of the chronology of the universe.

Physical cosmology is the study of the observable universe's origin, its large-scale structures and dynamics, and the ultimate fate of the universe, including the laws of science that govern these areas. It is investigated by scientists, including astronomers and physicists, as well as philosophers, such as metaphysicians, philosophers of physics, and philosophers of space and time. Because of this shared scope with philosophy, theories in physical cosmology may include both scientific and non-scientific propositions and may depend upon assumptions that cannot be tested. Physical cosmology is a sub-branch of astronomy that is concerned with the universe as a whole. Modern physical cosmology is dominated by the Big Bang Theory which attempts to bring together observational astronomy and particle physics; more specifically, a standard parameterization of the Big Bang with dark matter and dark energy, known as the Lambda-CDM model.

Aristotle (Attic Greek: Ἀριστοτέλης, romanized: Aristotélēs; 384–322 BC) was an ancient Greek philosopher and polymath. His writings cover a broad range of subjects spanning the natural sciences, philosophy, linguistics, economics, politics, psychology, and the arts. As the founder of the Peripatetic school of philosophy in the Lyceum in Athens, he began the wider Aristotelian tradition that followed, which set the groundwork for the development of modern science.

Little is known about Aristotle's life. He was born in the city of Stagira in northern Greece during the Classical period. His father, Nicomachus, died when Aristotle was a child, and he was brought up by a guardian. At around eighteen years old, he joined Plato's Academy in Athens and remained there until the age of thirty seven (c. 347 BC). Shortly after Plato died, Aristotle left Athens and, at the request of Philip II of Macedon, tutored his son Alexander the Great beginning in 343 BC. He established a library in the Lyceum, which helped him to produce many of his hundreds of books on papyrus scrolls.

In semiotics, khôra (also chora; Ancient Greek: χώρα) is the space that gives a place for being. The term has been used in philosophy by Plato to designate a receptacle (as a "third kind" [triton genos]; Timaeus 48e4), a space, a material substratum, or an interval. In Plato's account, khôra is described as a formless interval, alike to a non-being, in between which the "Forms" were received from the intelligible realm (where they were originally held) and were "copied", shaping into the transitory forms of the sensible realm; it "gives space" and has maternal overtones (a womb, matrix):

Humans, scientifically known as Homo sapiens, are primates that belong to the biological family of great apes and are characterized by hairlessness, bipedality, and high intelligence. Humans have large brains compared to body size, enabling more advanced cognitive skills that facilitate successful adaptation to varied environments, development of sophisticated tools, and formation of complex social structures and civilizations.

Humans are highly social, with individual humans tending to belong to a multi-layered network of distinct social groups – from families and peer groups to corporations and political states. As such, social interactions between humans have established a wide variety of values, social norms, languages, and traditions (collectively termed institutions), each of which bolsters human society. Humans are also highly curious: the desire to understand and influence phenomena has motivated humanity's development of science, technology, philosophy, mythology, religion, and other frameworks of knowledge; humans also study themselves through such domains as anthropology, social science, history, psychology, and medicine. As of 2025, there are estimated to be more than 8 billion living humans.

Reason is the capacity of consciously applying logic by drawing valid conclusions from new or existing information, with the aim of seeking truth. It is associated with such characteristically human activities as philosophy, religion, science, language, and mathematics, and is normally considered to be a distinguishing ability possessed by humans. Reason is sometimes referred to as rationality, although the latter is more about its application.

Reasoning involves using more-or-less rational processes of thinking and cognition to extrapolate from one's existing knowledge to generate new knowledge, and involves the use of one's intellect. The field of logic studies the ways in which humans can use formal reasoning to produce logically valid arguments and true conclusions. Reasoning may be subdivided into forms of logical reasoning, such as deductive reasoning, inductive reasoning, and abductive reasoning.

Epistemology is the branch of philosophy that examines the nature, origin, and limits of knowledge. Also called the theory of knowledge, it explores different types of knowledge, such as propositional knowledge about facts, practical knowledge in the form of skills, and knowledge by acquaintance as a familiarity through experience. Epistemologists study the concepts of belief, truth, and justification to understand the nature of knowledge. To discover how knowledge arises, they investigate sources of justification, such as perception, introspection, memory, reason, and testimony.

The school of skepticism questions the human ability to attain knowledge, while fallibilism says that knowledge is never certain. Empiricists hold that all knowledge comes from sense experience, whereas rationalists believe that some knowledge does not depend on it. Coherentists argue that a belief is justified if it coheres with other beliefs. Foundationalists, by contrast, maintain that the justification of basic beliefs does not depend on other beliefs. Internalism and externalism debate whether justification is determined solely by mental states or also by external circumstances.

Ethics is the philosophical study of moral phenomena. Also called moral philosophy, it investigates normative questions about what people ought to do or which behavior is morally right. Its main branches include normative ethics, applied ethics, and metaethics.

Normative ethics aims to find general principles that govern how people should act. Applied ethics examines concrete ethical problems in real-life situations, such as abortion, treatment of animals, and business practices. Metaethics explores the underlying assumptions and concepts of ethics. It asks whether there are objective moral facts, how moral knowledge is possible, and how moral judgments motivate people. Influential normative theories are consequentialism, deontology, and virtue ethics. According to consequentialists, an act is right if it leads to the best consequences. Deontologists focus on acts themselves, saying that they must adhere to duties, like telling the truth and keeping promises. Virtue ethics sees the manifestation of virtues, like courage and compassion, as the fundamental principle of morality.

Metaphysics is the branch of philosophy that examines the basic structure of reality. It is traditionally seen as the study of mind-independent features of the world, but some theorists view it as an inquiry into the conceptual framework of human understanding. Some philosophers, including Aristotle, designate metaphysics as first philosophy to suggest that it is more fundamental than other forms of philosophical inquiry.

Logic is the study of correct reasoning. It includes both formal and informal logic. Formal logic is the study of deductively valid inferences or logical truths. It examines how conclusions follow from premises based on the structure of arguments alone, independent of their topic and content. Informal logic is associated with informal fallacies, critical thinking, and argumentation theory. Informal logic examines arguments expressed in natural language whereas formal logic uses formal language. When used as a countable noun, the term "a logic" refers to a specific logical formal system that articulates a proof system. Logic plays a central role in many fields, such as philosophy, mathematics, computer science, and linguistics.

Logic studies arguments, which consist of a set of premises that leads to a conclusion. An example is the argument from the premises "it's Sunday" and "if it's Sunday then I don't have to work" leading to the conclusion "I don't have to work." Premises and conclusions express propositions or claims that can be true or false. An important feature of propositions is their internal structure. For example, complex propositions are made up of simpler propositions linked by logical vocabulary like ${\displaystyle \land }$ (and) or ${\displaystyle \to }$ (if...then). Simple propositions also have parts, like "Sunday" or "work" in the example. The truth of a proposition usually depends on the meanings of all of its parts. However, this is not the case for logically true propositions. They are true only because of their logical structure independent of the specific meanings of the individual parts.

Aesthetics is the branch of philosophy that studies beauty, taste, and related phenomena. In a broad sense, it includes the philosophy of art, which examines the nature of art, artistic creativity, the meanings of artworks, and audience appreciation.

Aesthetic properties are features that influence the appeal of objects. They include aesthetic values, which express positive or negative qualities, like the contrast between beauty and ugliness. Philosophers debate whether aesthetic properties have objective existence or depend on the subjective experiences of observers. According to a common view, aesthetic experiences are associated with disinterested pleasure detached from practical concerns. Taste is a subjective sensitivity to aesthetic qualities, and differences in taste can lead to disagreements about aesthetic judgments.

Ancient Roman philosophy is philosophy as it was practiced in the Roman Republic and its successor state, the Roman Empire. Roman philosophy includes philosophy written in Latin as well as philosophy written in Greek in the late Republic and Roman Empire. Important early Latin-language writers include Lucretius, Cicero, and Seneca the Younger. Greek was a popular language for writing about philosophy, so much so that the Roman Emperor Marcus Aurelius chose to write his Meditations in Greek.

Early Islamic philosophy or classical Islamic philosophy is a period of intense philosophical development beginning in the 2nd century AH of the Islamic calendar (early 9th century CE) and lasting until the 6th century AH (late 12th century CE). The period is known as the Islamic Golden Age, and the achievements of this period had a crucial influence in the development of modern philosophy and science. For Renaissance Europe, "Muslim maritime, agricultural, and technological innovations, as well as much East Asian technology via the Muslim world, made their way to western Europe in one of the largest technology transfers in world history." This period starts with al-Kindi in the 9th century and ends with Averroes (Ibn Rushd) at the end of 12th century. The death of Averroes effectively marks the end of a particular discipline of Islamic philosophy usually called the Peripatetic Arabic School, and philosophical activity declined significantly in Western Islamic countries, namely in Islamic Spain and North Africa, though it persisted for much longer in the Eastern countries, in particular Persia and India where several schools of philosophy continued to flourish: Avicennism, Illuminationist philosophy, Mystical philosophy, and Transcendent theosophy.

Intellectual innovations, achievements, and advancements of this period included, within jurisprudence, the development of ijtihad, a method or methodological approach to legal reasoning, interpretation, and argument based on independent inquiry and analogical deduction; within science and the philosophy of science, the development of empirical research methods emphasizing controlled experimentation, observational evidence, and reproducibility, as well as early formulations of empiricist epistemologies; commentaries and developments in Aristotelian logic, as well as innovations in non-Aristotelian temporal modal logic and inductive logic; and developments in research practice and methodology, including, within medicine, the first documented peer review process and within jurisprudence and theology, a strict science of citation, the isnad or "backing".

Sophia, or Sofia (Koine Greek: σοφία, sophía—"wisdom") is a central idea in Hellenistic philosophy and religion, Platonism, and Gnosticism. Originally carrying a meaning of "cleverness, skill", the later meaning of the term, close to the meaning of phronesis ("wisdom, intelligence"), was significantly shaped by the term philosophía ("love of wisdom") as used by Plato.

In the Orthodox Church and the Catholic Church, the feminine personification of divine wisdom as Holy Wisdom (Ἁγία Σοφία; Hagía Sophía) can refer either to Jesus Christ the Word of God (as in the dedication of the church of Hagia Sophia in Constantinople) or to the Holy Spirit.

Eastern philosophy (also called Asian philosophy or Oriental philosophy) includes the various philosophies that originated in East and South Asia, including Chinese philosophy, Japanese philosophy, Korean philosophy, and Vietnamese philosophy, which are dominant in East Asia; and Indian philosophy (including Hindu philosophy, Jain philosophy, Buddhist philosophy), which are dominant in South Asia, Southeast Asia, Tibet, Japan and Mongolia.

Natural philosophy or philosophy of nature (from Latin philosophia naturalis) is the philosophical study of physics, that is, nature and the physical universe, while ignoring any supernatural influence. It was dominant before the development of modern science.

From the ancient world (at least since Aristotle) until the 19th century, natural philosophy was the common term for the study of physics (nature), a broad term that included botany, zoology, anthropology, and chemistry as well as what is now called physics. It was in the 19th century that the concept of science received its modern shape, with different subjects within science emerging, such as astronomy, biology, and physics. Institutions and communities devoted to science were founded. Isaac Newton's book Philosophiæ Naturalis Principia Mathematica (1687) (English: Mathematical Principles of Natural Philosophy) reflects the use of the term natural philosophy in the 17th century. Even in the 19th century, the work that helped define much of modern physics bore the title Treatise on Natural Philosophy (1867).