Mind in the context of "Mind–body problem"

Philosophy (from Ancient Greek philosophía lit. 'love of wisdom') is a systematic study of general and fundamental questions concerning topics like existence, knowledge, mind, reason, language, and value. It is a rational and critical inquiry that reflects on its methods and assumptions.

Historically, many of the individual sciences, such as physics and psychology, formed part of philosophy. However, they are considered separate academic disciplines in the modern sense of the term. Influential traditions in the history of philosophy include Western, Arabic–Persian, Indian, and Chinese philosophy. Western philosophy originated in Ancient Greece and covers a wide area of philosophical subfields. A central topic in Arabic–Persian philosophy is the relation between reason and revelation. Indian philosophy combines the spiritual problem of how to reach enlightenment with the exploration of the nature of reality and the ways of arriving at knowledge. Chinese philosophy focuses principally on practical issues about right social conduct, government, and self-cultivation.

Ontology is the philosophical study of being. It is traditionally understood as the subdiscipline of metaphysics focused on the most general features of reality. As one of the most fundamental concepts, being encompasses all of reality and every entity within it. To articulate the basic structure of being, ontology examines the commonalities among all things and investigates their classification into basic types, such as the categories of particulars and universals. Particulars are unique, non-repeatable entities, such as the person Socrates, whereas universals are general, repeatable entities, like the color green. Another distinction exists between concrete objects existing in space and time, such as a tree, and abstract objects existing outside space and time, like the number 7. Systems of categories aim to provide a comprehensive inventory of reality by employing categories such as substance, property, relation, state of affairs, and event.

Ontologists disagree regarding which entities exist at the most basic level. Platonic realism asserts that universals have objective existence, while conceptualism maintains that universals exist only in the mind, and nominalism denies their existence altogether. Similar disputes pertain to mathematical objects, unobservable objects assumed by scientific theories, and moral facts. Materialism posits that fundamentally only matter exists, whereas dualism asserts that mind and matter are independent principles. According to some ontologists, objective answers to ontological questions do not exist, with perspectives shaped by differing linguistic practices.

Existence is the state of having being or reality in contrast to nonexistence and nonbeing. Existence is often contrasted with essence: the essence of an entity is its essential features or qualities, which can be understood even if one does not know whether the entity exists.

Ontology is the philosophical discipline studying the nature and types of existence. Singular existence is the existence of individual entities while general existence refers to the existence of concepts or universals. Entities present in space and time have concrete existence in contrast to abstract entities, like numbers and sets. Other distinctions are between possible, contingent, and necessary existence and between physical and mental existence. The common view is that an entity either exists or not with nothing in between, but some philosophers say that there are degrees of existence, meaning that some entities exist to a higher degree than others.

Psychology is the scientific study of behavior and mind. Its subject matter includes the behavior of humans and nonhumans, both conscious and unconscious phenomena, and mental processes such as thoughts, feelings, and motives. Psychology is an academic discipline of immense scope, crossing the boundaries between the natural and social sciences. Biological psychologists seek an understanding of the emergent properties of brains, linking the discipline to neuroscience. As social scientists, psychologists aim to understand the behavior of individuals and groups.

A professional practitioner or researcher involved in the discipline is called a psychologist. Some psychologists can also be classified as behavioral or cognitive scientists. Some psychologists attempt to understand the role of mental functions in individual and social behavior. Others explore the physiological and neurobiological processes that underlie cognitive functions and behaviors.

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.

The meaning of spirituality has developed and expanded over time, and various meanings can be found alongside each other. Traditionally, spirituality referred to a religious process of re-formation which "aims to recover the original shape of man", oriented at "the image of God" as exemplified by the founders and sacred texts of the religions of the world. The term was used within early Christianity to refer to a life oriented toward the Holy Spirit and broadened during the Late Middle Ages to include mental aspects of life.

In modern times, the term has spread to other religious traditions. It broadened to refer to a wider range of experiences, including a range of esoteric and religious traditions. Modern usages tend to refer to a subjective experience of a sacred dimension, and the "deepest values and meanings by which people live", often in a context separate from organized religious institutions. This may involve belief in a supernatural realm beyond the ordinarily observable world, personal growth, a quest for an ultimate or sacred meaning, religious experience, or an encounter with one's own "inner dimension" or spirit.

Semiotics is the study of signs. It is an interdisciplinary field that examines what signs are, how they form sign systems, and how individuals use them to communicate meaning. Its main branches are syntactics, which addresses formal relations between signs, semantics, which addresses the relation between signs and their meanings, and pragmatics, which addresses the relation between signs and their users. Semiotics is related to linguistics but has a broader scope that includes nonlinguistic signs, such as maps and clothing.

Signs are entities that stand for something else, like the word cat, which stands for a carnivorous mammal. They can take many forms, such as sounds, images, written marks, and gestures. Iconic signs operate through similarity. For them, the sign vehicle resembles the referent, such as a portrait of a person. Indexical signs are based on a direct physical link, such as smoke as a sign of fire. For symbolic signs, the relation between sign vehicle and referent is conventional or arbitrary, which applies to most linguistic signs. Models of signs analyze the basic components of signs. Ferdinand de Saussure's dyadic model identifies a perceptible image and a concept as the core elements, whereas Charles Sanders Peirce's triadic model distinguishes a sign vehicle, a referent, and an effect in the interpreter's mind.