Introduction | History of Idealism | Subjective Idealism | Transcendental Idealism | Objective Idealism | Absolute Idealism | Other Types of Idealism
Idealism is the metaphysical and epistemological doctrine that ideas or thoughts make up fundamental reality. Essentially, it is any philosophy which argues that the only thing actually knowable is consciousness (or the contents of consciousness), whereas we never can be sure that matter or anything in the outside world really exists. Thus, the only real things are mental entities, not physical things (which exist only in the sense that they are perceived).
Idealism is a form of Monism (as opposed to Dualism or Pluralism), and stands in direct contrast to other Monist beliefs such as Physicalism and Materialism (which hold that the only thing that can be truly proven to exist is physical matter). It is also contrasted with Realism (which holds that things have an absolute existence prior to, and independent of, our knowledge or perceptions).
A broad enough definition of Idealism could include many religious viewpoints, although an Idealistic viewpoint need not necessarily include God, supernatural beings, or an existence after death. It is a major tenet in the early Yogacara school of Buddhism, which developed into the mainstream Mahayana school. Some Hindu denominations are idealistic in outlook, although some have favoured a form of Dualism, as with Christianity.
In general parlance, "idealism" is also used to describe a person's high ideals (principles or values actively pursued as a goal), sometimes with the connotation that those ideals are unrealisable or impractical. The word "ideal" is also commonly used as an adjective to designate qualities of perfection, desirability and excellence, which is totally foreign to the epistemological use of the word "idealism", which pertains to internal mental representations.
Idealism is a label which covers a number of philosophical positions with quite different tendencies and implications, including Subjective Idealism, Objective Idealism, Transcendental Idealism and Absolute Idealism, as well as several more minor variants or related concepts (see the section on Other Types of Idealism below). Other labels which are essentially equivalent to Idealism include Mentalism and Immaterialism.
Plato is one of the first philosophers to discuss what might be termed Idealism, although his Platonic Idealism is, confusingly, usually referred to as Platonic Realism. This is because, although his doctrine described Forms or universals (which are certainly non-material "ideals" in a broad sense), Plato maintained that these Forms had their own independent existence, which is not an idealist stance, but a realist one. However, it has been argued that Plato believed that "full reality" (as distinct from mere existence) is achieved only through thought, and so he could be described as a non-subjective, "transcendental" idealist, somewhat like Kant.
The Neo-Platonist Plotinus came close to an early exposition of Idealism in the contentions in his "Enneads" that "the only space or place of the world is the soul", and that "time must not be assumed to exist outside the soul". However, his doctrine was not fully-realized, and he made no attempt to discover how we can get beyond our ideas in order to know external objects.
René Descartes was one of the first to claim that all we really know is what is in our own consciousnesses, and that the whole external world is merely an idea or picture in our minds. Therefore, he claimed, it is possible to doubt the reality of the external world as consisting of real objects, and “I think, therefore I am” is the only assertion that cannot be doubted. Thus, Descartes can be considered an early epistemological idealist.
Descartes' student, Nicolas Malebranche, refined this theory to state that we only directly know internally the ideas in our mind; anything external is the result of God's operations, and all activity only appears to occur in the external world. This kind of Idealism led to the Pantheism of Spinoza.
Gottfried Leibniz expressed a form of Idealism known as Panpsychism. He believed that the true atoms of the universe are monads, (individual, non-interacting "substantial forms of being", having perception). For Leibniz, the external world is ideal in that it is a spiritual phenomenon whose motion is the result of a dynamic force dependent on these simple and immaterial monads. God, the "central monad", created a pre-established harmony between the internal world in the minds of the alert monads, and the external world of real objects, so that the resulting world is essentially an idea of the monads’ perception.
Bishop George Berkeley is sometimes known as the "Father of Idealism", and he formulated one of the purest forms of Idealism in the early 18th Century. He argued that our knowledge must be based on our perceptions and that there was indeed no "real" knowable object behind one's perception (in effect, that what was "real" was the perception itself). He explained how it is that each of us apparently has much the same sort of perceptions of an object, by bringing in God as the immediate cause of all of our perceptions. Berkeley's version of Idealism is usually referred to as Subjective Idealism or Dogmatic Idealism (see the section below).
Arthur Collier (1680 - 1732), a near-contemporary and compatriot of Berkeley, published some very similar claims at around the same time (or even earlier), although the two were apparently not acquainted with, or influenced by, each other's work.
Immanuel Kant, the earliest and most influential member of the school of German Idealism, also started from the position of Berkeley's British Empiricism (that all we can know is the mental impressions or phenomena that an outside world creates in our minds). But he argued that the mind shapes the world as we perceive it to take the form of space-and-time. According to Kant, the mind is not a blank slate (or tabula rasa) as John Locke believed, but rather comes equipped with categories for organizing our sense impressions, even if we cannot actually approach the noumena (the "things-in-themselves") which emit or generate the phenomena (the "things-as-they-appear-to-us") that we perceive. Kant's Idealism is known as Transcendental Idealism (see the section below).
Johann Gottlieb Fichte denied Kant's concept of noumenon, arguing that the recognition of an external of any kind would be the same as admitting a real material thing. Instead, Fichte claimed that consciousness makes its own foundation, and does not have any grounding in a so-called "real world" (indeed, it is not grounded in anything outside of itself). He was the first to posit a theory of knowledge where absolutely nothing outside of thinking itself would be assumed to exist.
Friedrich Schelling also built on Berkeley and Kant's work and, along with Hegel, he developed Objective Idealism and the concept of the "The Absolute", which Hegel later developed further as Absolute Idealism.
G. W. F. Hegel was another of the famous German Idealists, and he argued that any doctrine (such as Materialism, for example) that asserts that finite qualities (or merely natural objects) are fully real is mistaken, because finite qualities depend on other finite qualities to determine them. Hegel called his philosophy Absolute Idealism (see the section below), in contrast to the Subjective Idealism of Berkeley and the Transcendental Idealism of Kant and Fichte, both of which doctrines he criticized. Although he took some of Kant's ideas seriously, Hegel based his doctrine more on Plato's belief that self-determination through the exercise of reason achieve a higher kind of reality than physical objects.
Another German Idealist, Arthur Schopenhauer, built on Kant's division of the universe into the phenomenal and the noumenal, suggesting that noumenal reality was singular whereas phenomenal experience involves multiplicity, and effectively argued that everything (however unlikely) is ultimately an act of will.
In the latter part of the 19th Century, British Idealism, led by F. H. Bradley (1846 - 1924), T. H. Green (1836 - 1882) and Bernard Bosanquet (1848 - 1923), continued to advocate Idealism in the face of strong opposition from the dominant Physicalist doctrines.
Subjective Idealism (or Solipsism or Subjectivism or Dogmatic Idealism or Immaterialism) is the doctrine that the mind and ideas are the only things that can be definitely known to exist or have any reality, and that knowledge of anything outside the mind is unjustified. Thus, objects exist by virtue of our perception of them, as ideas residing in our awareness and in the consciousness of the Divine Being, or God.
Its main proponent was the 18th Century Irish philosopher Bishop George Berkeley and he developed it out of the foundations of Empiricism which he shared with other British philosophers like John Locke and David Hume. Empiricism emphasizes the role of experience and sensory perception in the formation of ideas, while discounting the notion of innate ideas.
Berkeley believed that existence was tied to experience, and that objects exist only as perception and not as matter separate from perception. He claimed that "Esse est aut percipi aut percipere" or "To be is to be perceived or to perceive". Thus, the external world has only a relative and temporary reality. He argued that if he or another person saw a table, for example, then that table existed; however, if no one saw the table, then it could only continue to exist if it was in the mind of God. Berkeley further argued that it is God who causes us to experience physical objects by directly willing us to experience matter (thus avoiding the extra, unnecessary step of creating that matter).
Transcendental Idealism (or Critical Idealism) is the view that our experience of things is about how they appear to us (representations), not about those things as they are in and of themselves. Transcendental Idealism, generally speaking, does not deny that an objective world external to us exists, but argues that there is a supra-sensible reality beyond the categories of human reason which he called noumenon, roughly translated as the "thing-in-itself". However, we can know nothing of these "things-in-themselves" except that they can have no independent existence outside of our thoughts, although they must exist in order to ground the representations.
The doctrine was first introduced by Immanuel Kant (in his "Critique of Pure Reason") and was also espoused by Johann Gottlieb Fichte and Friedrich Schelling, and later resurrected in the 20th Century by Edmund Husserl.
This type of Idealism is considered "transcendental" in that we are in some respects forced into it by considering that our knowledge has necessary limitations, and that we can never know things as they really are, totally independent of us. The name may, however, be considered counter-intuitive and confusing, and Kant himself preferred the label Critical Idealism.
Objective Idealism is the view that the world "out there" is in fact Mind communicating with our human minds. It postulates that there is only one perceiver, and that this perceiver is one with that which is perceived. It accepts common sense Realism (the view that independent material objects exist), but rejects Naturalism (the view that the mind and spiritual values have emerged from material things).
Plato is regarded as one of the earliest representatives of Objective Idealism (although it can be argued that Plato's worldview was actually dualistic and not truly Idealistic). The definitive formulation of the doctrine came from the German Idealist Friedrich Schelling, and later adapted by G. W. F. Hegel in his Absolute Idealism theory. More recent advocates have included C. S. Peirce and Josiah Royce (1855 - 1916).
Schelling's Objective Idealism agrees with Berkeley that there is no such thing as matter in the materialist sense, and that spirit is the essence and whole of reality. However, he argued that there is a perfect parallel between the world of nature and the structure of our awareness of it. Although, this cannot be true of an individual ego, it can be true of an absolute consciousness. He also objected to the idea that God is separate from the world, arguing that reality is a single, absolute, all-inclusive mind, which he (and Hegel) referred to as "The Absolute Spirit" (or simply "The Absolute").
According to Objective Idealism, the Absolute is all of reality: no time, space, relation or event ever exists or occurs outside of it. As the Absolute also contains all possibilities in itself, it is not static, but constantly changing and progressing. Human beings, planets and even galaxies are not separate beings, but part of something larger, similar to the relation of cells or organs to the whole body.
A general objection to Idealism is that it is implausible and against common sense to think that there can be an analytic reduction of the physical to the mental. Hegel's system of Objective Idealism has also come under fire for merely substituting the Absolute for God, which does not make anything clearer in the end.
Absolute Idealism is the view, initially formulated by G. W. F. Hegel, that in order for human reason to be able to know the world at all, there must be, in some sense, an identity of thought and being; otherwise, we would never have any means of access to the world, and we would have no certainty about any of our knowledge. Like Plato many centuries before him, Hegel argued that the exercise of reason enables the reasoner to achieve a kind of reality (namely self-determination, or "reality as oneself") that mere physical objects like rocks can never achieve.
Hegel started from Kant's position that the mind can not know "things-in-themselves", and asserted that what becomes the real is "Geist" (mind, spirit or soul), which he sees as developing through history, each period having a "Zeitgeist" (spirit of the age). He also held that each person's individual consciousness or mind is really part of the Absolute Mind (even if the individual does not realize this), and he argued that if we understood that we were part of a greater consciousness we would not be so concerned with our individual freedom, and we would agree with to act rationally in a way that did not follow our individual caprice, thereby achieving self-fulfilment.
For Hegel, the interaction of opposites (or dialectics) generates all of the concepts we use in order to understand the world. This occurs both in the individual mind as well as through history. Thus, the absolute ground of being is essentially a dynamic, increasingly complex historical process of necessity that unfolds by itself, ultimately giving rise to all the diversity in the world and in the concepts with which we think and make sense of the world.
Hegel's doctine was later championed by F. H. Bradley (1846 - 1924) and the British Idealist movement, as well as Josiah Royce (1855 - 1916) in the USA.
Proponents of Analytic Philosophy, which has been the dominant form of Anglo-American philosophy for most of the 20th Century, have criticised Hegel's work as hopelessly obscure. Pragmatists like William James and F. C. S. Schiller have attacked Absolute Idealism for being too disconnected from our practical lives. G. E. Moore used common sense and logical analysis against the radically counter-intuitive conclusions of Absolute Idealism (e.g. that time is unreal, change is unreal, separateness is unreal, imperfection is unreal, etc).
Existentialists have also criticise Hegel for ultimately choosing an essentialistic whole over the particularity of existence. Schopenhauer objected that The Absolute is just a non-personal substitute for the concept of God. Another perennial problem of Hegel's metaphysics is the question of how spirit externalizes itself and how the concepts it generates can say anything true about nature; otherwise his system becomes just an intricate game involving vacuous concepts.
In addition to the main types of Idealism mentioned above, there are other types of Idealism:
- Epistemological Idealism asserts that minds are aware of, or perceive, only their own ideas (representations or mental images), and not external objects, and therefore we cannot directly know things in themselves, or things as they really are. All we can ever have knowledge about is the world of phenomenal human experience, and there is no reason to suspect that reality actually mirrors our perceptions and thoughts. This is very similar to the doctrine of Phenomenalism.
- Actual Idealism is a form of Idealism developed by the Italian philosopher Giovanni Gentile (1875 - 1944) that contrasted the Transcendental Idealism of Kant and the Absolute Idealism of Hegel. His system saw thought as all-embracing, and claimed that no-one could actually leave their sphere of thinking, or exceed their own thought. His ideas were key to helping the Fascist party consolidate power in Italy, and gave Fascism much of its philosophical base.
- Buddhist Idealism (also known as "consciousness-only" or "mind-only") is the concept in Buddhist thought that all existence is nothing but consciousness, and therefore there is nothing that lies outside of the mind. It is a major tenet in the early Yogacara school of Buddhism, which developed into the mainstream Mahayana school.
- Panpsychism holds that that all parts of matter involve mind or, alternatively, that the whole universe is an organism that possesses a mind. Therefore, according to Panpsychism, all objects of experience are also subjects (i.e. plants and minerals have subjective experiences, albeit very different from the consciousness of humans). Gottfried Leibniz subscribed to a view of this kind of Idealism.
- Practical Idealism is a political philosophy which holds it to be an ethical imperative to implement ideals of virtue or good (it is is therefore unrelated to Idealism in its other senses). Its earliest recorded use was by Mahatma Gandhi (1869 - 1948), although it is now often used in foreign policy and international relations, where it purports to be a pragmatic compromise between political realism (which stresses the promotion of a state's narrow and amoral self-interest), and political idealism (which aims to use the state's influence and power to promote higher liberal ideals like peace, justice and co-operation between nations).