In a broad sense, appearances are not limited to what people perceive but can also include memories, beliefs, and thoughts. Unreal entities, by contrast, depend for their existence on thoughts and ideas; they would not arise or would vanish without the mental activity creating or sustaining them. A related topic concerns the possibility and limits of knowledge as a successful cognitive contact with reality. Anti-realism, by contrast, holds that certain aspects of reality depend on mental processes, subjective perspectives, or social conventions.

Realism and anti-realism

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

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.
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.

Values

• Inspired by Leibniz, David Lewis (1941–2001) developed modal realism, maintaining that possible worlds are as real as the actual world.
• 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.
• In the broadest sense, being is the most general category that applies to everything and contrasts only with nothingness.
• On this view, unobservable entities may be invoked in theory construction to aid prediction but should not be taken to exist.
• In ancient Greek philosophy starting in the 6th century BCE, the pre-Socratics discussed the first principles from which all things arise.

Anti-realism about abstract objects in mathematics takes various forms, including, but not limited to, fictionalism. Anti-realists hold that there are no abstract objects and offer alternative explanations. Realists and anti-realists about abstract objects debate whether, or in what sense, such entities form part of reality. Nominalism, another anti-realist view, rejects both mental and non-mental interpretations of universals. For example, a person may be a realist about universals and an anti-realist about values. In this sense, realism and anti-realism encompass many domain-specific positions across diverse fields.

• Reality testing is another suggested psychological function in which individuals distinguish intrapsychic from external events to assess how their experience aligns with reality.
• It holds that this practice can be useful in some contexts without ascribing substantive or framework-independent reality to such entities.
• Naturalism argues that values are part of the natural world and can be studied by the natural sciences through empirical observation.
• Phenomenalism, a related view, reduces physical objects to collections of actual or possible sensory experiences.
• Local realism is a view that combines the principle of locality with the notion that there are definite physical properties, whether or not they are being observed by someone.

Values

For example, if a planet or a virus is real then it exists on its own and behaves according to its nature, even if people are unaware or hold false beliefs about it. Debates between realists and anti-realists span multiple domains, addressing the objective existence of universals, abstract objects, values, and unobservable entities posited by scientific theories. Realism is the view that reality does not depend on human knowledge or consciousness and exists apart from them. The concept of reality overlaps with notions such as being, existence, world, actuality, and truth. Tomi Lahren has blasted West Wilson over his views on transgender athletes. Influenced by Kant, Edmund Husserl (1859–1938) argued that reality is tied to consciousness as an intersubjective correlate of experience that cannot be reduced to a wholly mind-independent substrate.
Naturalism argues that values are part of the natural world and can be studied by the natural sciences through empirical observation. Some positions concern the existence of values in general, while others are limited to specific domains, such as moral, aesthetic, or religious values. Formalism, another form of anti-realism, understands mathematics as a practice of symbol manipulation, suggesting that mathematical truth is grounded in whether the manipulation rules permit the construction of a proof. According to conventionalism, the truth of mathematical statements rests on linguistic conventions or definitions, rather than on their relation to language-independent reality.
On this view, higher levels show greater complexity and new phenomena but depend on the lower ones and could not exist without them. https://www.zumospin.net/ 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.
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.
For example, psychologism asserts that mathematical objects are mental constructions or ideas rather than abstract objects. Fictionalists argue that discourse about abstract objects concerns fictional entities within make-believe frameworks. According to conceptualism, universals exist in the mind as concepts through which people categorize and order their impressions, acting as tools of cognitive organization rather than properties of external entities. Platonism about universals holds that they are part of reality in their own right, independent of the particular entities that instantiate them.
Accordingly, worldviews address not only theoretical matters but also practical and evaluative outlooks about what matters and how one should act. Another view maintains that they are real as digital objects with genuine existence and causal powers, residing within and being constituted by computational processes. Similarly, virtual reality worlds may incorporate real-world objects into the simulation or be entirely virtual.l Although it is not a widely accepted position, various thought experiments undermining the reliability of human cognitive faculties are discussed in the academic literature. It denies the existence of knowledge in any form or domain, arguing that knowledge is impossible. These limitations indicate a gap whereby reality is not fully captured and exceeds knowledge.

In China, beginning roughly in the 9th century, Neo-Confucianism maintained that reality has a rational order expressed in the principle Li, which acts as a ground of being. In ancient Greek philosophy starting in the 6th century BCE, the pre-Socratics discussed the first principles from which all things arise. The school of Vaisheshika arose roughly in the 2nd century BCE and developed a system of six fundamental categories of being. Various historiographical debates address the question of whether a truly objective account of the past is possible.

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.