Anti-realism rejects this view, arguing instead that there is no external world or that reality depends in certain respects on mental processes, subjective perspectives, or social conventions. Realism and anti-realism are families of views concerning the mind-independence of reality. Some interpretations of quantum mechanics hold that measurement outcomes are inherently probabilistic, thereby rejecting causal determinism, but this is not true for all interpretations.g According to this view, what happened in the past fixes what will happen in the future, including human behavior. Causal determinism is the view that every event is fully determined or necessitated by prior events. Laws of nature play a central role in the physical sciences by providing frameworks for predicting outcomes under specified conditions.

Realism and anti-realism

  • In ancient Greek philosophy starting in the 6th century BCE, the pre-Socratics discussed the first principles from which all things arise.
  • A semantic approach to the debate between realism and anti-realism, proposed by Michael Dummett, argues that the underlying disagreement concerns the meaning of statements rather than the existence of entities.
  • On this view, unobservable entities may be invoked in theory construction to aid prediction but should not be taken to exist.
  • In the broadest sense, being is the most general category that applies to everything and contrasts only with nothingness.
  • Inspired by Leibniz, David Lewis (1941–2001) developed modal realism, maintaining that possible worlds are as real as the actual world.
  • Realists and anti-realists about abstract objects debate whether, or in what sense, such entities form part of reality.

In psychoanalytic theory, the reality principle is a proposed mechanism that counteracts the pleasure principle, delaying immediate gratification when it collides with the demands of external reality. For example, value theory is concerned with the reality of values, and the philosophy of mathematics explores in what sense mathematical objects, like numbers and sets, form part of reality. Different worldviews offer distinct answers to existential questions about meaning, morality, and the nature of reality, such as the contrast between religious and secular worldviews. A worldview is a comprehensive framework for understanding reality and humanity’s place within it. One perspective holds that such objects are illusory or unreal because they lack existence in the physical world outside the simulation. The reality–virtuality continuum is a theoretical framework that posits a continuous scale of mixed reality forms.
For example, one view suggests that macroscopic objects, such as a chair, depend on the microscopic objects that underlie them, such as elementary particles. The structure of reality concerns the fundamental patterns of being, describing how entities are organized and interact with each other. According to a common view, concrete objects exist in space and time, such as a flower, a horse, and a ship. Events are proposed constituents of reality that occur in time, such as the discovery of penicillin and the Second World War.

  • One strand of the field analyzes culture-specific worldviews and compares them across societies.
  • A central topic in ontology is the categories of being—fundamental classes that map out a comprehensive inventory of reality.
  • It overlaps with the cognitive sciences, which investigate how cognitive processes transform information about the world, and with neuroscience, which studies the brain activities underlying such processes.
  • Immanuel Kant (1724–1804) rejected the possibility of objective knowledge of the things in themselves, arguing instead that all experience is shaped by the innate structures of human cognition.
  • This view emphasizes that reality is encountered, rather than invented, and can resist or frustrate beliefs and desires, unlike malleable imaginary creations.
  • It concerns the question of how mental and linguistic entities, such as thoughts and words, can establish contact with reality by successfully referring to things in the world.

In this sense, it is the state of being real or what all real entities have in common, separating them from unreal or illusory ones. In a slightly different sense, reality is not the totality itself but an aspect shared by all its constituents. Contemporary technology in the form of augmented and virtual reality can inform experience and raises questions about the ontological status of virtual objects. Other discussions examine space and time as frameworks that organize relations among entities, and laws of nature describing regularities or general patterns of how entities interact and changes unfold. Various criteria for distinguishing real from unreal entities have been proposed, including causal powers, mind-independence, and being non-illusory. It is often contrasted with appearance, opposing what is with what seems to be, although the accuracy and fundamentality of this contrast are disputed.

Related concepts

Mereological universalism holds that any collection of entities constitutes a whole, even if the entities are otherwise unrelated. Various theories of the mereological principles underlying composition have been proposed. For example, David Lewis’s modal realism asserts that there exist countless spatiotemporally unified possible worlds, each just as real as the actual world. A different view suggests that reality is made up of many worlds that exist in parallel to one another, each representing a distinct way of how things could have been. In a narrow sense, being contrasts with becoming, and denotes stable or permanent aspects of reality. Some philosophers, such as Alexius Meinong, hold that being is a broader concept than reality, encompassing nonexistent objects, such as merely possible or incomplete objects, in addition to real or actual ones.
It overlaps with the cognitive sciences, which investigate how cognitive processes transform information about the world, and with neuroscience, which studies the brain activities underlying such processes. It concerns the question of how mental and linguistic entities, such as thoughts and words, can establish contact with reality by successfully referring to things in the world. It focuses on how individuals experience reality and how conscious states are intentional or directed towards entities other than themselves. Epistemology, another philosophical subdiscipline, explores how people can know reality. They examine what it means for something to be real, how entities are divided into different categories of being, and which entities exist at the most fundamental level.
On this view, unobservable entities may be invoked in theory construction to aid prediction but should not be taken to exist. Scientific realism is the view that the best scientific theories provide an accurate description of a mind-independent world. Error theory asserts that all value statements are false because there are no values.i Another form of anti-realism maintains that value statements are neither true nor false but meaningless. According to subjectivism, values depend on the attitudes and preferences of individuals. Non-naturalism, another form of realism, maintains that values differ significantly from empirical properties and belong to another domain of reality.

Levels of reality

On this view, higher levels show greater complexity and new phenomena but depend on the lower ones and could not exist without them. Some philosophical approaches rely on the idea of fundamentality and dependence to analyze the world in terms of levels or layers, such as material, biological, psychological, and social reality. In the Hindu tradition, it is often identified with Brahman as the all-pervasive reality and the supreme principle grounding all being. Some outlooks suggest that only the fundamental level is ultimately real, arguing that non-fundamental entities are in some sense eliminable since reality can be described without them.
This view emphasizes that reality is encountered, rather than invented, and can resist or frustrate beliefs and desires, unlike malleable imaginary creations. Another influential proposal treats mind-independence as a criterion of reality, arguing that real entities do not depend on how people think about them. The Eleatic principle is controversial because it is typically taken to deny that abstract objects studied in fields like mathematics, such as numbers, are real. However, stories about Santa Claus, such as written texts in children’s books, are part of reality since they can influence https://www.zumospin.net/ how people think. Discussed in ancient Greek philosophy as the Eleatic principle, it states that to be real is to be able to produce changes and to be affected by them. Criteria of reality are proposed features or standards that distinguish real entities from unreal ones.

Values

In the broadest sense, being is the most general category that applies to everything and contrasts only with nothingness. The term reality overlaps with various related concepts, such as being, existence, world, actuality, and truth. This view contrasts being real with being fake, like the distinction between a real duck and a fake one used as a decoy.

It holds that the debate is not based on a substantive disagreement but arises instead from conceptual confusions. For example, metaphysical idealism asserts that everything is essentially mental, for instance, by understanding material objects as ideas in the mind. In this sense, reality does not depend on human knowledge or consciousness and exists apart from them, including the aspects that no one is aware of. The widely accepted Big Bang theory holds that the universe began about 13.8 billion years ago, initially in an extremely hot, dense state, expanding and cooling ever since.

Levels of reality

As individual entities, they contrast with universals, which are general, repeatable entities that can have many instances, such as the color blue, the shape roundness, and the property of being a mammal. Various categories of being or constituents of reality are discussed in the academic discourse. Similarly, the many-worlds interpretation of quantum physics suggests that in quantum measurements, not only one but all possible outcomes occur, interpreted as a branching of the universe into multiple worlds. It is often contrasted with essence, which denotes the nature or characteristic features of an entity.
A central topic in ontology is the categories of being—fundamental classes that map out a comprehensive inventory of reality. Becoming, by contrast, covers change, like when an entity shifts from one state of being to another. Other suggested criteria identify reality with what is observable, measurable,a coherent,b useful, objective, intersubjective, or fundamental. It focuses on how things seem to be, distinguishing real appearances, which are as they seem, from illusory ones, which are not as they seem.
Monism and pluralism are families of views about the roles of unity and multiplicity in the structure of reality. According to this view, even a complete understanding of physics would not render sciences dedicated to higher levels, such as psychology, obsolete. Non-reductive physicalists hold that everything is ultimately physical while insisting that higher-level psychological facts cannot be reduced to fundamental physics. In this sense, there can be matter without biological life, whereas life is built upon matter and depends on it. Lower levels, by contrast, operate according to more basic mechanisms and are prior to the higher ones.