Subjective idealism

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George Berkeley is credited with the development of subjective idealism. George Berkeley by John Smibert.jpg
George Berkeley is credited with the development of subjective idealism.

Subjective idealism, or empirical idealism, is the monistic metaphysical doctrine that only minds and mental contents exist. It entails and is generally identified or associated with immaterialism, the doctrine that material things do not exist. Subjective idealism rejects dualism, neutral monism, and materialism; indeed, it is the contrary of eliminative materialism, the doctrine that all or some classes of mental phenomena (such as emotions, beliefs, or desires) do not exist, but are sheer illusions.



Subjective idealism is a fusion of phenomenalism or empiricism, which confers special status upon the immediately perceived, with idealism, which confers special status upon the mental. Idealism denies the knowability or existence of the non-mental, while phenomenalism serves to restrict the mental to the empirical. Subjective idealism thus identifies its mental reality with the world of ordinary experience, rather than appealing to the unitary world-spirit of pantheism or absolute idealism. This form of idealism is "subjective" not because it denies that there is an objective reality, but because it asserts that this reality is completely dependent upon the minds of the subjects that perceive it.

The earliest thinkers identifiable as subjective idealists were certain members of the Yogācāra school of Indian Buddhism, who reduced the world of experience to a stream of subjective perceptions. Subjective idealism made its mark in Europe in the 18th-century writings of George Berkeley, who argued that the idea of mind-independent reality is incoherent, concluding that the world consists of the minds of humans and of God. Subsequent writers have continuously grappled with Berkeley's skeptical arguments. Immanuel Kant responded by rejecting Berkeley's immaterialism and replacing it with transcendental idealism, which views the mind-independent world as existent but incognizable in itself. Since Kant, true immaterialism has remained a rarity, but is survived by partly overlapping movements such as phenomenalism, subjectivism, and perspectivism.


Thinkers such as Plato, Plotinus and Augustine of Hippo anticipated idealism's antimaterialism [ disambiguation needed ] with their views of the inferior or derivative reality of matter. However, these Platonists did not make Berkeley's turn toward subjectivity. Plato helped anticipate these ideas by creating an analogy about people living in a cave which explained his point of view. His view was that there are different types of reality. He explains this with his cave analogy which contains people tied up only seeing shadows their whole life. Once they go outside, they see a completely different reality, but lose sight of the one they saw before [1] . This sets up the idea of Berkley’s theory of immaterialism because it shows how people can be exposed to the same world but still see things differently. This introduces the idea of objective versus subjective which is how Berkeley proves that matter does not exist. Indeed, Plato rationalistically condemned sense-experience, whereas subjective idealism presupposed empiricism and the irreducible reality of sense data. A more subjectivist methodology could be found in the Pyrrhonists' emphasis on the world of appearance, but their skepticism precluded the drawing of any ontological conclusions from the epistemic primacy of phenomena.

The first mature articulations of idealism arise in Yogacarin thinkers such as the 7th-century epistemologist Dharmakīrti, who identified ultimate reality with sense-perception. The most famous proponent of subjective idealism in the Western world was the 18th-century Irish philosopher George Berkeley, although Berkeley's term for his theory was immaterialism. From the point of view of subjective idealism, the material world does not exist, and the phenomenal world is dependent on humans. Hence the fundamental idea of this philosophical system (as represented by Berkeley or Mach) is that things are complexes of ideas or sensations, and only subjects and objects of perceptions exist. "Esse est percipi" is Berkeley’s whole argument summarized into a couple words. It means “to be is to be perceived” [2] . This summarized his argument because he based his point around the fact that things exist if they are all understood and seen the same way. As Berkeley wrote: “for the Existence of an Idea consists in being perceived” [3] . This would separate everything as objective and subjective. Matter falls into the subjective category because everyone perceives matter differently which mean matter is not real. This loops back to the core of his argument which says that in order for anything to be real, it must be interpreted the same way by everyone.

Berkeley believes that all material is a construction by the human mind. According to the Stanford Encyclopedia of Philosophy his argument is: “(1) We perceive ordinary objects (houses, mountains, etc.). (2) We perceive only ideas. Therefore, (3) Ordinary objects are ideas.” [4]

Berkeley makes such a radical claim that matter does not exist as a reaction to the materialists. He says “if there were external bodies, we couldn’t possibly come to know this; and if there weren’t, we might have the very same reasons to think there were that we have now”: [5] “a thinking being might, without the help of external bodies, be affected with the same series of sensations or ideas as you have.” [5] Berkeley believes that people cannot know that what they think to be matter is not simply a creation in their mind.

People have contested that premise (2) is false, claiming that people don't perceive ideas but instead, “distinguishing two sorts of perception” [6] they perceive objects and then have ideas about them, effectively cutting down the equality. This might seem to obviously be the case, but in fact it is contestable. Many psychologists believe that what people actually perceive are tools, impediments, and threats. The famous gorilla psychological study, where people were asked to watch a video and count the number of basketball passes made, showed that people do not actually see everything in front of them, even a gorilla that marches across a high school gym. [7] Similarly, it is believed that human reaction to snakes is faster than it should physically be if it were consciously driven. Therefore, it is not unfair to say that objects go straight to the mind.

Berkeley even pointed out that it is not obvious how motion in the physical world could translate to emotion in the mind. Even the materialists had difficulty explaining this; Locke believed that to explain the transfer from physical object to mental image one must “attribute it wholly to the good pleasure of our Maker.” [8] Newton's laws of physics say that all movement comes from the inverse change in another motion, and materialists believe that what humans do is fundamentally move their parts. Then how you explain the correlation between objects existing, and the completely other realm of regular ideas is not obvious. The fact “that the existence of matter does not help to explain the occurrence of our ideas” [6] seems to Berkeley to undermine the reason for believing in matter at all. If the materialists have no way of knowing that matter exists, it seems best to not assume that it exists.

According to Berkeley, an object has real being as long as it is perceived by a mind. God, being omniscient perceives everything perceivable, thus all real beings exist in the mind of God. However, it is also evident that each of us has free will and understanding upon self-reflection, and our senses and ideas suggest that other people also possess these qualities as well. According to Berkeley there is no material universe, in fact he has absolutely no idea what that could possibly mean. To theorize about a universe that is composed of insensible matter is not a sensible thing to do. This matters because there is absolutely no positive account for a material universe, only speculation about things that are by fiat outside of our minds.

Berkeley's assessment of immaterialism was criticized by Samuel Johnson, as recorded by James Boswell. Responding to the theory, Dr. Johnson exclaimed "I refute it thus!" while kicking a rock with "mighty force". This episode is alluded to by Stephen Dedalus in James Joyce's Ulysses, chapter three. Reflecting on the "ineluctable modality of the visible", Dedalus conjures the image of Johnson's refutation and carries it forth in conjunction with Aristotle's expositions on the nature of the senses as described in Sense and Sensibilia . Aristotle held that while visual perception suffered a compromised authenticity because it passed through the diaphanous liquid of the inner eye before being observed, sound and the experience of hearing were not thus similarly diluted. Dedalus experiments with the concept in the development of his aesthetic ideal.

In fiction

Subjective idealism is featured prominently in the Norwegian novel Sophie's World , in which "Sophie's world" exists in fact only in the pages of a book.[ citation needed ]

A parable of subjective idealism can be found in Jorge Luis Borges' short story Tlön, Uqbar, Orbis Tertius , which specifically mentions Berkeley.

See also

Related Research Articles

In philosophy, empiricism is a theory that states that knowledge comes only or primarily from sensory experience. It is one of several views of epistemology, the study of human knowledge, along with rationalism and skepticism. Empiricism emphasises the role of empirical evidence in the formation of ideas, rather than innate ideas or traditions. However, empiricists may argue that traditions arise due to relations of previous sense experiences.

George Berkeley Anglo-Irish philosopher

George Berkeley – known as Bishop Berkeley – was an Irish philosopher whose primary achievement was the advancement of a theory he called "immaterialism". This theory denies the existence of material substance and instead contends that familiar objects like tables and chairs are only ideas in the minds of perceivers and, as a result, cannot exist without being perceived. Berkeley is also known for his critique of abstraction, an important premise in his argument for immaterialism.

Idealism philosophical view that reality is immaterial

In philosophy, idealism is the diverse group of metaphysical philosophies which assert that "reality" is in some way indistinguishable or inseparable from human understanding and/or perception; that it is in some sense mentally constituted, or otherwise closely connected to ideas. According to Immanuel Kant, a pioneer of modern idealist thought, idealism does “not concern the existence of things”, but asserts only that our “modes of representation” of them, above all space and time, are not “determinations that belong to things in themselves” but essential features of our own minds. Kant called this position “transcendental” and “critical” idealism, since it describes the way in which "reality" is utterly transcended by, and cannot be thought separate from, the categories with which they are structered by and in human understanding.

Materialism is a form of philosophical monism that holds that matter is the fundamental substance in nature, and that all things, including mental states and consciousness, are results of material interactions. According to philosophical materialism, mind and consciousness are by-products or epiphenomena of material processes, without which they cannot exist. This concept directly contrasts with idealism, where mind and consciousness are first-order realities to which matter is subject and material interactions are secondary.

Mind Combination of cognitive faculties that provide consciousness, thinking, reasoning, perception and judgement

The mind is the set of cognitive faculties including consciousness, imagination, perception, thinking, judgement, language and memory, which is housed in the brain. It is usually defined as the faculty of an entity's thoughts and consciousness. It holds the power of imagination, recognition, and appreciation, and is responsible for processing feelings and emotions, resulting in attitudes and actions.


The philosophy of perception is concerned with the nature of perceptual experience and the status of perceptual data, in particular how they relate to beliefs about, or knowledge of, the world. Any explicit account of perception requires a commitment to one of a variety of ontological or metaphysical views. Philosophers distinguish internalist accounts, which assume that perceptions of objects, and knowledge or beliefs about them, are aspects of an individual's mind, and externalist accounts, which state that they constitute real aspects of the world external to the individual. The position of naïve realism—the 'everyday' impression of physical objects constituting what is perceived—is to some extent contradicted by the occurrence of perceptual illusions and hallucinations and the relativity of perceptual experience as well as certain insights in science. Realist conceptions include phenomenalism and direct and indirect realism. Anti-realist conceptions include idealism and skepticism.

Platonic realism philosophical term

Platonic realism is the philosophical position that universals or abstract objects exist objectively and outside of human minds. It is named after the Greek philosopher Plato who applied realism to such universals, which he considered ideal forms. This stance is ambiguously also called Platonic idealism but should not be confused with idealism as presented by philosophers such as George Berkeley: as Platonic abstractions are not spatial, temporal, or mental, they are not compatible with the later idealism's emphasis on mental existence. Plato's Forms include numbers and geometrical figures, making them a theory of mathematical realism; they also include the Form of the Good, making them in addition a theory of ethical realism.

Reality is the sum or aggregate of all that is real or existent within a system, as opposed to that which is only imaginary. The term is also used to refer to the ontological status of things, indicating their existence. In physical terms, reality is the totality of a system, known and unknown. Philosophical questions about the nature of reality or existence or being are considered under the rubric of ontology, which is a major branch of metaphysics in the Western philosophical tradition. Ontological questions also feature in diverse branches of philosophy, including the philosophy of science, philosophy of religion, philosophy of mathematics, and philosophical logic. These include questions about whether only physical objects are real, whether reality is fundamentally immaterial, whether hypothetical unobservable entities posited by scientific theories exist, whether God exists, whether numbers and other abstract objects exist, and whether possible worlds exist.

Solipsism is the philosophical idea that only one's mind is sure to exist. As an epistemological position, solipsism holds that knowledge of anything outside one's own mind is unsure; the external world and other minds cannot be known and might not exist outside the mind.

Mind–body dualism Philosophical theory that mental phenomena are non-physical and that matter exists independently of mind

Mind–body dualism is the view in the philosophy of mind that mental phenomena are non-physical, or that the mind and body are distinct and separable. Thus, it encompasses a set of views about the relationship between mind and matter, and between subject and object, and is contrasted with other positions, such as physicalism and enactivism, in the mind–body problem.

Phenomenalism is the view that physical objects cannot justifiably be said to exist in themselves, but only as perceptual phenomena or sensory stimuli situated in time and in space. In particular, some forms of phenomenalism reduce talk about physical objects in the external world to talk about bundles of sense-data.

<i>Critique of Pure Reason</i> 1781 book by Immanuel Kant

The Critique of Pure Reason is a book by the German philosopher Immanuel Kant, in which the author seeks to determine the limits and scope of metaphysics. Also referred to as Kant's "First Critique", it was followed by the Critique of Practical Reason (1788) and the Critique of Judgment (1790). In the preface to the first edition, Kant explains that by a "critique of pure reason" he means a critique "of the faculty of reason in general, in respect of all knowledge after which it may strive independently of all experience" and that he aims to reach a decision about "the possibility or impossibility of metaphysics".

Objective idealism is an idealistic metaphysics that postulates that there is in an important sense only one perceiver, and that this perceiver is one with that which is perceived. One important advocate of such a metaphysics, Josiah Royce, wrote that he was indifferent "whether anybody calls all this Theism or Pantheism". It is distinct from the subjective idealism of George Berkeley, and it abandons the thing-in-itself of Kant's dualism.

Panpsychism View that mind or a mind-like aspect is a fundamental and ubiquitous feature of reality

In philosophy of mind, panpsychism is the view that mind or a mind-like aspect is a fundamental and ubiquitous feature of reality. It has taken on a wide variety of forms. Contemporary academic proponents hold that sentience or subjective experience is ubiquitous, while distancing these qualities from complex human mental attributes; they ascribe a primitive form of mentality to entities at the fundamental level of physics but do not ascribe it to most aggregates, such as rocks or buildings. On the other hand, some historical theorists ascribed attributes such as life or spirits to all entities.

In metaphysics, realism about a given object is the view that this object exists in reality independently of our conceptual scheme. In philosophical terms, these objects are ontologically independent of someone's conceptual scheme, perceptions, linguistic practices, beliefs, etc.

Neopragmatism, sometimes called post-Deweyan pragmatism, linguistic pragmatism, or analytic pragmatism, is the philosophical tradition that infers that the meaning of words is a function of how they are used, rather than the meaning of what people intend for them to describe.

<i>Three Dialogues between Hylas and Philonous</i> treatise by treatise

Three Dialogues between Hylas and Philonous, or simply Three Dialogues, is a 1713 book on metaphysics and idealism written by George Berkeley. Taking the form of a dialogue, the book was written as a response to the criticism Berkeley experienced after publishing A Treatise Concerning the Principles of Human Knowledge.

Mind–body problem Open question in philosophy of how abstract minds interact with physical bodies

The mind–body problem is a debate concerning the relationship between thought and consciousness in the human mind, and the brain as part of the physical body. It is distinct from the question of how mind and body function chemically and physiologically, as that question presupposes an interactionist account of mind–body relations. This question arises when mind and body are considered as distinct, based on the premise that the mind and the body are fundamentally different in nature.

The following outline is provided as an overview of and topical guide to metaphysics:

Objectivity is a philosophical concept of being true independently from individual subjectivity caused by perception, emotions, or imagination. A proposition is considered to have objective truth when its truth conditions are met without bias caused by a sentient subject. Scientific objectivity refers to the ability to judge without partiality or external influence, sometimes used synonymously with neutrality.


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