George Berkeley (/ˈbɑːrkli/; 12 March 1685 – 14 January 1753) – known as Bishop Berkeley (Bishop of Cloyne) – was an Irish philosopher whose primary achievement was the advancement of a theory he called "immaterialism" (later referred to as "subjective idealism" by others). 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.
In 1709, Berkeley published his first major work, An Essay towards a New Theory of Vision, in which he discussed the limitations of human vision and advanced the theory that the proper objects of sight are not material objects, but light and colour. This foreshadowed his chief philosophical work, A Treatise Concerning the Principles of Human Knowledge, in 1710, which, after its poor reception, he rewrote in dialogue form and published under the title Three Dialogues between Hylas and Philonous in 1713.
In this book, Berkeley's views were represented by Philonous (Greek: "lover of mind"), while Hylas (Greek: "matter") embodies the Irish thinker's opponents, in particular John Locke. Berkeley argued against Isaac Newton's doctrine of absolute space, time and motion in De Motu (On Motion), published 1721. His arguments were a precursor to the views of Mach and Einstein. In 1732, he published Alciphron, a Christian apologetic against the free-thinkers, and in 1734, he published The Analyst, a critique of the foundations of calculus, which was influential in the development of mathematics.
His last major philosophical work, Siris (1744), begins by advocating the medicinal use of tar water and then continues to discuss a wide range of topics, including science, philosophy, and theology. Interest in Berkeley's work increased after World War II because he tackled many of the issues of paramount interest to philosophy in the 20th century, such as the problems of perception, the difference between primary and secondary qualities, and the importance of language.
Portrait of Berkeley by John Smybert, 1727
|Born||12 March 1685|
County Kilkenny, Ireland
|Died||14 January 1753 (aged 67)|
|Alma mater||Trinity College, Dublin|
|School||Subjective idealism (phenomenalism)|
|Christianity, metaphysics, epistemology, language, mathematics, perception|
|Subjective idealism, master argument, a priori/a posteriori distinction|
Berkeley was born at his family home, Dysart Castle, near Thomastown, County Kilkenny, Ireland, the eldest son of William Berkeley, a cadet of the noble family of Berkeley. Little is known of his mother. He was educated at Kilkenny College and attended Trinity College, Dublin, where he was elected a Scholar in 1702, earning a bachelor's degree in 1704 and completing a master's degree in 1707. He remained at Trinity College after completion of his degree as a tutor and Greek lecturer.
His earliest publication was on mathematics, but the first that brought him notice was his An Essay towards a New Theory of Vision, first published in 1709. In the essay, Berkeley examines visual distance, magnitude, position and problems of sight and touch. While this work raised much controversy at the time, its conclusions are now accepted as an established part of the theory of optics.
The next publication to appear was the Treatise Concerning the Principles of Human Knowledge in 1710, which had great success and gave him a lasting reputation, though few accepted his theory that nothing exists outside the mind. This was followed in 1713 by Three Dialogues between Hylas and Philonous, in which he propounded his system of philosophy, the leading principle of which is that the world, as represented by our senses, depends for its existence on being perceived.
For this theory, the Principles gives the exposition and the Dialogues the defence. One of his main objectives was to combat the prevailing materialism of his time. The theory was largely received with ridicule, while even those such as Samuel Clarke and William Whiston, who did acknowledge his "extraordinary genius," were nevertheless convinced that his first principles were false.
Shortly afterwards, Berkeley visited England and was received into the circle of Addison, Pope and Steele. In the period between 1714 and 1720, he interspersed his academic endeavours with periods of extensive travel in Europe, including one of the most extensive Grand Tours of the length and breadth of Italy ever undertaken. In 1721, he took Holy Orders in the Church of Ireland, earning his doctorate in divinity, and once again chose to remain at Trinity College Dublin, lecturing this time in Divinity and in Hebrew. In 1721/2 he was made Dean of Dromore and, in 1724, Dean of Derry.
In 1723, following her violent quarrel with Jonathan Swift, who had been her intimate friend for many years, Esther Vanhomrigh (for whom Swift had created the nickname "Vanessa") named Berkeley her co-heir along with the barrister Robert Marshall; her choice of legatees caused a good deal of surprise since she did not know either of them well, although Berkeley as a very young man had known her father. Swift said generously that he did not grudge Berkeley his inheritance, much of which vanished in a lawsuit in any event. A story that Berkeley and Marshall disregarded a condition of the inheritance that they must publish the correspondence between Swift and Vanessa is probably untrue.
In 1725, he began the project of founding a college in Bermuda for training ministers and missionaries in the colony, in pursuit of which he gave up his deanery with its income of £1100.
In 1728, he married Anne Forster, daughter of John Forster, Chief Justice of the Irish Common Pleas, and his first wife Rebecca Monck. He then went to America on a salary of £100 per annum. He landed near Newport, Rhode Island, where he bought a plantation at Middletown – the famous "Whitehall". It has been claimed that "he introduced Palladianism into America by borrowing a design from [William] Kent's Designs of Inigo Jones for the door-case of his house in Rhode Island, Whitehall." He also brought to New England John Smibert, the British artist he "discovered" in Italy, who is generally regarded as the founding father of American portrait painting. Meanwhile, he drew up plans for the ideal city he planned to build on Bermuda. He lived at the plantation while he waited for funds for his college to arrive. The funds, however, were not forthcoming, and in 1732 he left America and returned to London. He and Anne had four children who survived infancy: Henry, George, William and Julia, and at least two other children who died in infancy. William's death in 1751 was a great cause of grief to his father.
While living in London's Saville Street, he took part in efforts to create a home for the city's abandoned children. The Foundling Hospital was founded by Royal Charter in 1739, and Berkeley is listed as one of its original governors.
His last two publications were Siris: A Chain of Philosophical Reflexions and Inquiries Concerning the Virtues of Tarwater, And divers other Subjects connected together and arising one from another (1744) and Further Thoughts on Tar-water (1752). Pine tar is an effective antiseptic and disinfectant when applied to cuts on the skin, but Berkeley argued for the use of pine tar as a broad panacea for diseases. His 1744 work on tar-water sold more copies than any of his other books during Berkeley's lifetime.
He remained at Cloyne until 1752, when he retired. With his wife and daughter Julia he went to Oxford to live with his son George and supervise his education. He died soon afterward and was buried in Christ Church Cathedral, Oxford. His affectionate disposition and genial manners made him much loved and held in warm regard by many of his contemporaries. Anne outlived her husband by many years, and died in 1786.
According to Berkeley there are only two kinds of things: spirits and ideas. Spirits are simple, active beings which produce and perceive ideas; ideas are passive beings which are produced and perceived.
The use of the concepts of "spirit" and "idea" is central in Berkeley's philosophy. As used by him, these concepts are difficult to translate into modern terminology. His concept of "spirit" is close to the concept of "conscious subject" or of "mind", and the concept of "idea" is close to the concept of "sensation" or "state of mind" or "conscious experience".
Thus Berkeley denied the existence of matter as a metaphysical substance, but did not deny the existence of physical objects such as apples or mountains. ("I do not argue against the existence of any one thing that we can apprehend, either by sense or reflection. That the things I see with mine eyes and touch with my hands do exist, really exist, I make not the least question. The only thing whose existence we deny, is that which philosophers call matter or corporeal substance. And in doing of this, there is no damage done to the rest of mankind, who, I dare say, will never miss it.", Principles #35) This basic claim of Berkeley's thought, his "idealism", is sometimes and somewhat derisively called "immaterialism" or, occasionally, subjective idealism. In Principles #3, he wrote, using a combination of Latin and English, esse is percipi (to be is to be perceived), most often if slightly inaccurately attributed to Berkeley as the pure Latin phrase esse est percipi. The phrase appears associated with him in authoritative philosophical sources, e.g., "Berkeley holds that there are no such mind-independent things, that, in the famous phrase, esse est percipi (aut percipere) – to be is to be perceived (or to perceive)."
Hence, human knowledge is reduced to two elements: that of spirits and of ideas (Principles #86). In contrast to ideas, a spirit cannot be perceived. A person's spirit, which perceives ideas, is to be comprehended intuitively by inward feeling or reflection (Principles #89). For Berkeley, we have no direct 'idea' of spirits, albeit we have good reason to believe in the existence of other spirits, for their existence explains the purposeful regularities we find in experience. ("It is plain that we cannot know the existence of other spirits otherwise than by their operations, or the ideas by them excited in us", Dialogues #145). This is the solution that Berkeley offers to the problem of other minds. Finally, the order and purposefulness of the whole of our experience of the world and especially of nature overwhelms us into believing in the existence of an extremely powerful and intelligent spirit that causes that order. According to Berkeley, reflection on the attributes of that external spirit leads us to identify it with God. Thus a material thing such as an apple consists of a collection of ideas (shape, color, taste, physical properties, etc.) which are caused in the spirits of humans by the spirit of God.
A convinced adherent of Christianity, Berkeley believed God to be present as an immediate cause of all our experiences.
He did not evade the question of the external source of the diversity of the sense data at the disposal of the human individual. He strove simply to show that the causes of sensations could not be things, because what we called things, and considered without grounds to be something different from our sensations, were built up wholly from sensations. There must consequently be some other external source of the inexhaustible diversity of sensations. The source of our sensations, Berkeley concluded, could only be God; He gave them to man, who had to see in them signs and symbols that carried God's word.
Here is Berkeley's proof of the existence of God:
Whatever power I may have over my own thoughts, I find the ideas actually perceived by Sense have not a like dependence on my will. When in broad daylight I open my eyes, it is not in my power to choose whether I shall see or no, or to determine what particular objects shall present themselves to my view; and so likewise as to the hearing and other senses; the ideas imprinted on them are not creatures of my will. There is therefore some other Will or Spirit that produces them. (Berkeley. Principles #29)
As T.I. Oizerman explained:
Berkeley's mystic idealism (as Kant aptly christened it) claimed that nothing separated man and God (except materialist misconceptions, of course), since nature or matter did not exist as a reality independent of consciousness. The revelation of God was directly accessible to man, according to this doctrine; it was the sense-perceived world, the world of man's sensations, which came to him from on high for him to decipher and so grasp the divine purpose.
Berkeley believed that God is not the distant engineer of Newtonian machinery that in the fullness of time led to the growth of a tree in the university quadrangle. Rather, the perception of the tree is an idea that God's mind has produced in the mind, and the tree continues to exist in the quadrangle when "nobody" is there, simply because God is an infinite mind that perceives all.
The philosophy of David Hume concerning causality and objectivity is an elaboration of another aspect of Berkeley's philosophy. A.A. Luce, the most eminent Berkeley scholar of the 20th century, constantly stressed the continuity of Berkeley's philosophy. The fact that Berkeley returned to his major works throughout his life, issuing revised editions with only minor changes, also counts against any theory that attributes to him a significant volte-face.
John Locke (Berkeley's predecessor) states that we define an object by its primary and secondary qualities. He takes heat as an example of a secondary quality. If you put one hand in a bucket of cold water, and the other hand in a bucket of warm water, then put both hands in a bucket of lukewarm water, one of your hands is going to tell you that the water is cold and the other that the water is hot. Locke says that since two different objects (both your hands) perceive the water to be hot and cold, then the heat is not a quality of the water.
While Locke used this argument to distinguish primary from secondary qualities, Berkeley extends it to cover primary qualities in the same way. For example, he says that size is not a quality of an object because the size of the object depends on the distance between the observer and the object, or the size of the observer. Since an object is a different size to different observers, then size is not a quality of the object. Berkeley rejects shape with a similar argument and then asks: if neither primary qualities nor secondary qualities are of the object, then how can we say that there is anything more than the qualities we observe?
In his Essay Towards a New Theory of Vision, Berkeley frequently criticised the views of the Optic Writers, a title that seems to include Molyneux, Wallis, Malebranche and Descartes. In sections 1–51, Berkeley argued against the classical scholars of optics by holding that: spatial depth, as the distance that separates the perceiver from the perceived object is itself invisible. That is, we do not see space directly or deduce its form logically using the laws of optics. Space for Berkeley is no more than a contingent expectation that visual and tactile sensations will follow one another in regular sequences that we come to expect through habit.
Berkeley goes on to argue that visual cues, such as the perceived extension or 'confusion' of an object, can only be used to indirectly judge distance, because the viewer learns to associate visual cues with tactile sensations. Berkeley gives the following analogy regarding indirect distance perception: one perceives distance indirectly just as one perceives a person's embarrassment indirectly. When looking at an embarrassed person, we infer indirectly that the person is embarrassed by observing the red color on the person's face. We know through experience that a red face tends to signal embarrassment, as we've learned to associate the two.
The question concerning the visibility of space was central to the Renaissance perspective tradition and its reliance on classical optics in the development of pictorial representations of spatial depth. This matter was debated by scholars since the 11th-century Arab polymath and mathematician Alhazen (al-Hasan Ibn al-Haytham) affirmed in experimental contexts the visibility of space. This issue, which was raised in Berkeley's theory of vision, was treated at length in the Phenomenology of Perception of Maurice Merleau-Ponty, in the context of confirming the visual perception of spatial depth (la profondeur), and by way of refuting Berkeley's thesis.
Berkeley wrote about the perception of size in addition to that of distance. He is frequently misquoted as believing in size–distance invariance – a view held by the Optic Writers. This idea is that we scale the image size according to distance in a geometrical manner. The error may have become commonplace because the eminent historian and psychologist E. G. Boring perpetuated it. In fact, Berkeley argued that the same cues that evoke distance also evoke size, and that we do not first see size and then calculate distance. It is worth quoting Berkeley's words on this issue (Section 53):
What inclines men to this mistake (beside the humour of making one see by geometry) is, that the same perceptions or ideas which suggest distance, do also suggest magnitude... I say they do not first suggest distance, and then leave it to the judgement to use that as a medium, whereby to collect the magnitude; but they have as close and immediate a connexion with the magnitude as with the distance; and suggest magnitude as independently of distance, as they do distance independently of magnitude.
"Berkeley's works display his keen interest in natural philosophy [...] from his earliest writings (Arithmetica, 1707) to his latest (Siris, 1744). Moreover, much of his philosophy is shaped fundamentally by his engagement with the science of his time." The profundity of this interest can be judged from numerous entries in Berkeley's Philosophical Commentaries (1707–1708), e.g. "Mem. to Examine & accurately discuss the scholium of the 8th Definition of Mr Newton's Principia." (#316)
Berkeley argued that forces and gravity, as defined by Newton, constituted "occult qualities" that "expressed nothing distinctly". He held that those who posited "something unknown in a body of which they have no idea and which they call the principle of motion, are in fact simply stating that the principle of motion is unknown." Therefore, those who "affirm that active force, action, and the principle of motion are really in bodies are adopting an opinion not based on experience." Forces and gravity existed nowhere in the phenomenal world. On the other hand, if they resided in the category of "soul" or "incorporeal thing", they "do not properly belong to physics" as a matter. Berkeley thus concluded that forces lay beyond any kind of empirical observation and could not be a part of proper science. He proposed his theory of signs as a means to explain motion and matter without reference to the "occult qualities" of force and gravity.
Berkeley's razor is a rule of reasoning proposed by the philosopher Karl Popper in his study of Berkeley's key scientific work De Motu. Berkeley's razor is considered by Popper to be similar to Ockham's razor but "more powerful". It represents an extreme, empiricist view of scientific observation that states that the scientific method provides us with no true insight into the nature of the world. Rather, the scientific method gives us a variety of partial explanations about regularities that hold in the world and that are gained through experiment. The nature of the world, according to Berkeley, is only approached through proper metaphysical speculation and reasoning. Popper summarises Berkeley's razor as such:
A general practical result – which I propose to call "Berkeley's razor" – of [Berkeley's] analysis of physics allows us a priori to eliminate from physical science all essentialist explanations. If they have a mathematical and predictive content they may be admitted qua mathematical hypotheses (while their essentialist interpretation is eliminated). If not they may be ruled out altogether. This razor is sharper than Ockham's: ALL entities are ruled out except those which are perceived.
In addition to his contributions to philosophy, Berkeley was also very influential in the development of mathematics, although in a rather indirect sense. "Berkeley was concerned with mathematics and its philosophical interpretation from the earliest stages of his intellectual life." Berkeley's "Philosophical Commentaries" (1707–1708) witness to his interest in mathematics:
Axiom. No reasoning about things whereof we have no idea. Therefore no reasoning about Infinitesimals. (#354)
Take away the signs from Arithmetic & Algebra, & pray what remains? (#767)
These are sciences purely Verbal, & entirely useless but for Practise in Societys of Men. No speculative knowledge, no comparison of Ideas in them. (#768)
In 1707, Berkeley published two treatises on mathematics. In 1734, he published The Analyst, subtitled A DISCOURSE Addressed to an Infidel Mathematician, a critique of calculus. Florian Cajori called this treatise "the most spectacular event of the century in the history of British mathematics." However, a recent study suggests that Berkeley misunderstood Leibnizian calculus. The mathematician in question is believed to have been either Edmond Halley, or Isaac Newton himself—though if to the latter, then the discourse was posthumously addressed, as Newton died in 1727. The Analyst represented a direct attack on the foundations and principles of calculus and, in particular, the notion of fluxion or infinitesimal change, which Newton and Leibniz used to develop the calculus. In his critique, Berkeley coined the phrase "ghosts of departed quantities", familiar to students of calculus. Ian Stewart's book From Here to Infinity captures the gist of his criticism.
Berkeley regarded his criticism of calculus as part of his broader campaign against the religious implications of Newtonian mechanics – as a defence of traditional Christianity against deism, which tends to distance God from His worshipers. Specifically, he observed that both Newtonian and Leibnizian calculus employed infinitesimals sometimes as positive, nonzero quantities and other times as a number explicitly equal to zero. Berkeley's key point in "The Analyst" was that Newton's calculus (and the laws of motion based in calculus) lacked rigorous theoretical foundations. He claimed that
In every other Science Men prove their Conclusions by their Principles, and not their Principles by the Conclusions. But if in yours you should allow your selves this unnatural way of proceeding, the Consequence would be that you must take up with Induction, and bid adieu to Demonstration. And if you submit to this, your Authority will no longer lead the way in Points of Reason and Science.
Berkeley did not doubt that calculus produced real world truth; simple physics experiments could verify that Newton's method did what it claimed to do. "The cause of Fluxions cannot be defended by reason", but the results could be defended by empirical observation, Berkeley's preferred method of acquiring knowledge at any rate. Berkeley, however, found it paradoxical that "Mathematicians should deduce true Propositions from false Principles, be right in Conclusion, and yet err in the Premises." In The Analyst he endeavoured to show "how Error may bring forth Truth, though it cannot bring forth Science". Newton's science, therefore, could not on purely scientific grounds justify its conclusions, and the mechanical, deistic model of the universe could not be rationally justified.
The difficulties raised by Berkeley were still present in the work of Cauchy whose approach to calculus was a combination of infinitesimals and a notion of limit, and were eventually sidestepped by Weierstrass by means of his (ε, δ) approach, which eliminated infinitesimals altogether. More recently, Abraham Robinson restored infinitesimal methods in his 1966 book Non-standard analysis by showing that they can be used rigorously.
The tract A Discourse on Passive Obedience (1712) is considered Berkeley's major contribution to moral and political philosophy.
In A Discourse on Passive Obedience, Berkeley defends the thesis that people have "a moral duty to observe the negative precepts (prohibitions) of the law, including the duty not to resist the execution of punishment." However, Berkeley does make exceptions to this sweeping moral statement, stating that we need not observe precepts of "usurpers or even madmen" and that people can obey different supreme authorities if there are more than one claims to the highest authority.
Berkeley defends this thesis with a deductive proof stemming from the laws of nature. First, he establishes that because God is perfectly good, the end to which he commands humans must also be good, and that end must not benefit just one person, but the entire human race. Because these commands—or laws—if practiced, would lead to the general fitness of humankind, it follows that they can be discovered by the right reason—for example, the law to never resist supreme power can be derived from reason because this law is "the only thing that stands between us and total disorder". Thus, these laws can be called the laws of nature, because they are derived from God—the creator of nature himself. "These laws of nature include duties never to resist the supreme power, lie under oath...or do evil so that good may come of it."
One may view Berkeley’s doctrine on Passive Obedience as a kind of 'Theological Utilitarianism', insofar as it states that we have a duty to uphold a moral code which presumably is working towards the ends of promoting the good of humankind. However, the concept of 'ordinary' Utilitarianism is fundamentally different in that it "makes utility the one and only ground of obligation"—that is, Utilitarianism is concerned with whether particular actions are morally permissible in specific situations, while Berkeley’s doctrine is concerned with whether or not we should follow moral rules in any and all circumstances. Whereas Utilitarianism might, for example, justify a morally impermissible act in light of the specific situation, Berkeley’s doctrine of Passive Obedience holds that it is never morally permissible to not follow a moral rule, even when it seems like breaking that moral rule might achieve the happiest ends. Berkeley holds that even though sometimes, the consequences of an action in a specific situation might be bad, the general tendencies of that action benefits humanity.
Other important sources for Berkeley's views on morality are Alciphron (1732), especially dialogues I–III, and the Discourse to Magistrates (1738)." Passive Obedience is notable partly for containing one of the earliest statements of rule utilitarianism.
George Berkeley’s theory that matter does not exist comes from the belief that "sensible things are those only which are immediately perceived by sense." Berkeley says in his book called The Principles of Human Knowledge that “the ideas of sense are stronger, livelier, and clearer than those of the imagination; and they are also steady, orderly and coherent."  From this we can tell that the things that we are perceiving are truly real rather than it just being a dream.
All knowledge comes from perception; what we perceive are ideas, not things in themselves; a thing in itself must be outside experience; so the world only consists of ideas and minds that perceive those ideas; a thing only exists so far as it perceives or is perceived. Through this we can see that consciousness is considered something that exists to Berkeley due to its ability to perceive. "'To be,' said of the object, means to be perceived; 'to be,' said of the subject, means to perceive or "esse est percipi." " Having established this, Berkeley then attacks the “opinion strangely prevailing amongst men, that houses, mountains, rivers, and in a world all sensible objects have an existence natural or real, distinct from being perceived.”  He believes this idea to be inconsistent because such an object with an existence independent of perception must have both sensible qualities, and thus be known (making it an idea), and also an insensible reality, which Berkeley believes is inconsistent.  Berkeley believes that the error arises because people think that perceptions can imply or infer something about the material object. Berkeley calls this concept abstract ideas. He rebuts this concept by arguing that people cannot conceive of an object without also imagining the sensual input of the object. He argues in Principles of Human Knowledge that, similar to how people can only sense matter with their senses through the actual sensation, they can only conceive of matter (or, rather, ideas of matter) through the idea of sensation of matter.  This implies that everything that people can conceive in regards to matter is only ideas about matter. Thus, matter, should it exist, must exist as collections of ideas, which can be perceived by the senses and interpreted by the mind. But if matter is just a collection of ideas, then Berkeley concludes that matter, functionally, does not exist (or at least, not in the way that most philosophers of Berkeley’s time believed). Indeed, if a person visualizes something, then it must have some color, however dark or light; it cannot just be a shape of no color at all if a person is to visualize it.  But matter ought not to have inherent color, as well as smell or sound or taste; these properties are only the senses’ interpretation of matter. Therefore, matter, should it actually exist, is, at the very least, not knowable. Berkeley’s ideas raised controversy because his argument refuted Descartes' worldview, which was expanded upon by Locke, and resulted in the rejection of Berkeley’s form of empiricism by several philosophers of the seventeenth and eighteenth centuries. In Locke’s worldview, "the world causes the perceptual ideas we have of it by the way it interacts with our senses." This contradicts with Berkeley's worldview because not only does it suggest the existence of physical causes in the world, but in fact there is no physical world beyond our ideas. The only causes that exist in Berkeley’s worldview are those that are a result of the use of the will.
Berkeley’s theory relies heavily on his form of empiricism, which in turn relies heavily on the senses. His empiricism can be defined by five propositions: all significant words stand for ideas; all knowledge is about our ideas; all ideas come from without or from within; if from without it must be by the senses, and they are called sensations, if from within they are the operations of the mind, and are called thoughts. Berkeley clarifies his distinction between ideas by saying they "are imprinted on the senses," "perceived by attending to the passions and operations of the mind," or "are formed by help of memory and imagination." One refutation of his idea was: if someone leaves a room and stops perceiving that room does that room no longer exist? Berkeley answers this by claiming that it is still being perceived and the consciousness that is doing the perceiving is God. (This makes Berkeley’s argument hinge upon an omniscient, omnipresent deity.) This claim is the only thing holding up his argument which is "depending for our knowledge of the world, and of the existence of other minds, upon a God that would never deceive us." Berkeley anticipates a second objection, which he refutes in Principles of Human Knowledge. He anticipates that the materialist may take a representational materialist standpoint: although the senses can only perceive ideas, these ideas resemble (and thus can be compared to) the actual, existing object. Thus, through the sensing of these ideas, the mind can make inferences as to matter itself, even though pure matter is non-perceivable. Berkeley’s objection to that notion is that “an idea can be like nothing but an idea; a color or figure can be like nothing but another color or figure.”  Berkeley distinguishes between an idea, which is mind-dependent, and a material object, which is not an idea and is mind-independent. As they are not alike, they cannot be compared, just as one cannot compare the color red to something that is invisible, or the sound of music to silence, other than that one exists and the other does not. This is called the likeness principle: the notion that an idea can only be like (and thus compared to) another idea. If this principle is granted, then material objects lose any kind of association to the attributes that the senses give them.  Since matter, should it exist, is not related to the ideas perceived by the senses according to the likeness principle, Berkeley argues that the existence of the idea is all that a person can know. Therefore, it is illogical to conclude that, because the idea of matter exists, matter itself exists. This justifies Berkeley’s skepticism regarding the existence of matter.
Berkeley's Treatise Concerning the Principles of Human Knowledge was published three years before the publication of Arthur Collier's Clavis Universalis, which made assertions similar to those of Berkeley's. However, there seemed to have been no influence or communication between the two writers.
German philosopher Arthur Schopenhauer once wrote of him: "Berkeley was, therefore, the first to treat the subjective starting-point really seriously and to demonstrate irrefutably its absolute necessity. He is the father of idealism...".
Today, every student of the history of philosophy is familiar with the view that there was a sort of linear development involving three great "British Empiricists", leading from Locke through Berkeley to Hume.
Berkeley influenced many modern philosophers, especially David Hume. Thomas Reid admitted that he put forward a drastic criticism of Berkeleianism after he had been an admirer of Berkeley's philosophical system for a long time. Berkeley's "thought made possible the work of Hume and thus Kant, notes Alfred North Whitehead." Some authors draw a parallel between Berkeley and Edmund Husserl.
When Berkeley visited America, the American educator Samuel Johnson visited him, and the two later corresponded. Johnson convinced Berkeley to establish a scholarship program at Yale, and to donate a large number of books as well as his plantation to the college when the philosopher returned to England. It was one of Yale's largest and most important donations; it doubled its library holdings, improved the college's financial position and brought Anglican religious ideas and English culture into New England. Johnson also took Berkeley's philosophy and used parts of it as a framework for his own American Practical Idealism school of philosophy. As Johnson's philosophy was taught to about half the graduates of American colleges between 1743 and 1776, and over half of the contributors to the Declaration of Independence were connected to it, Berkeley's ideas were indirectly a foundation of the American Mind.
Outside of America, during Berkeley's lifetime his philosophical ideas were comparatively uninfluential. But interest in his doctrine grew from the 1870s when Alexander Campbell Fraser, "the leading Berkeley scholar of the nineteenth century", published "The Works of George Berkeley." A powerful impulse to serious studies in Berkeley's philosophy was given by A. A. Luce and Thomas Edmund Jessop, "two of the twentieth century's foremost Berkeley scholars," thanks to whom Berkeley scholarship was raised to the rank of a special area of historico-philosophical science. In addition, the philosopher Colin Murray Turbayne wrote extensively on Berkeley's use of language as model for visual, physiological, natural and metaphysical relationships.
The proportion of Berkeley scholarship, in literature on the history of philosophy, is increasing. This can be judged from the most comprehensive bibliographies on George Berkeley. During the period of 1709–1932, about 300 writings on Berkeley were published. That amounted to 1.5 publication per annum. During the course of 1932–79, over one thousand works were brought out, i.e., 20 works per annum. Since then, the number of publications has reached 30 per annum. In 1977 publication began in Ireland of a special journal on Berkeley's life and thought (Berkeley Studies). Similarly, in 1988, the Australian philosopher Colin Murray Turbayne established the International Berkeley Essay Prize Competition at the University of Rochester in an effort to advance scholarship and research on the works of George Berkeley in the future. 
Other than philosophy, Berkeley also influenced modern psychology with his work on John Locke's theory of association and how it could be used to explain how humans gain knowledge in the physical world. He also used the theory to explain perception, stating that all qualities where, as Locke would call them, secondary qualities therefore perception laid entirely in the perceiver and not in the object. These are both topics today studied in modern psychology.
The University of California, Berkeley, was named after him, although the pronunciation has evolved to suit American English: (/ˈbɜːrkli/ BURK-lee). The naming was suggested in 1866 by Frederick Billings, a trustee of the then College of California. Billings was inspired by Berkeley's Verses on the Prospect of Planting Arts and Learning in America, particularly the final stanza: "Westward the course of empire takes its way; The first four Acts already past, A fifth shall close the Drama with the day; Time's noblest offspring is the last."
On 18 April 1735, The Town of Berkley, currently the least populated town in Bristol County, Massachusetts, was founded and named after the renowned philosopher. Located 40 miles south of Boston and 25 miles north of Middletown (Rhode Island), where Berkeley lived at his farmhouse, Whitehall Museum House remains today to commemorate the farmhouse modified by Dean George Berkeley when he lived in the northern section of Newport, Rhode Island (that comprises present-day Middletown, Rhode Island) in 1729–31, while working to open his planned St Paul's College on the island of Bermuda. It is also known as Berkeley House (or Bishop George Berkeley House), and was listed on the National Register of Historic Places in 1970.
Also named for him is Berkeley Preparatory School in Tampa, Florida. This leading private school is affiliated with the Episcopal Church, has almost 1300 students from pre-kindergarten through twelfth grade, and was founded in 1960.
An Ulster History Circle blue plaque commemorating him is located in Bishop Street Within, city of Derry.
"Bishop Berkeley's Gold Medals" are two awards given annually at Trinity College Dublin, "provided outstanding merit is shown", to candidates answering a special examination in Greek. The awards were founded in 1752 by Berkeley who was a Fellow in 1707–24.
The Works of George Berkeley. Ed. by Alexander Campbell Fraser. In 4 Volumes. Oxford: Clarendon Press, 1901.
Ewald, William B., ed., 1996. From Kant to Hilbert: A Source Book in the Foundations of Mathematics, 2 vols. Oxford Uni. Press.
Events from the year 1685 in Ireland.Berkeley College (Yale University)
Berkeley College is a residential college at Yale University, opened in 1934. The eighth of Yale's 14 residential colleges, it was named in honor of Reverend George Berkeley (1685–1753), dean of Derry and later bishop of Cloyne, in recognition of the assistance in land and books that he gave to Yale in the 18th century. Built on the site of a group of buildings known from the 1890s until 1933 as the Berkeley Oval, the college was renovated in 1998.Berkeley Studies
Berkeley Studies (Berkeley Newsletter until December 2007) is an annual on-line academic journal established in 1977. It publishes scholarly articles on anything related to George Berkeley. The journal also gives news of the last events in Berkeley scholarship: book reviews, information about coming pertinent conferences, and abstracts from reports delivered at such conferences. Assembling bibliography on Berkeley constitutes an essential part of the editors' work.The first issue of the journal was published and distributed by the Philosophy Department at Trinity College, Dublin. When Hampden-Sydney College hosted the journal's web site in 2005, issues started to be published in the new format of an online journal. The previous issues were digitized and are available for free download in PDF format.
While publishing papers in English, the journal welcomes review articles on the reception of Berkeley's philosophy in non-English-speaking countries.Berkeley Studies is sponsored by Hampden-Sydney College and the International Berkeley Society, but editorial operations are independent from both.British philosophy
British philosophy refers to the philosophical tradition of the British people. "The native characteristics of British philosophy are these: common sense, dislike of complication, a strong preference for the concrete over the abstract and a certain awkward honesty of method in which an occasional pearl of poetry is embedded".Custos Rotulorum of Gloucestershire
This is a list of people who have served as Custos Rotulorum of Gloucestershire.
Sir Edmund Tame bef. 1544–1544
Sir Anthony Kingston 1544?–1556
Sir Nicholas Arnold bef. 1558–1580
Sir Thomas Throckmorton bef. 1584 – 1602 (deprived of office)
Sir John Poyntz 1602 – aft. 1608
Grey Brydges, 5th Baron Chandos bef. 1621–1621
Sir John Bridgeman 1621–1638
Thomas Coventry, 1st Baron Coventry 1638–1640
George Berkeley, 1st Earl of Berkeley 1660–1689
Charles Berkeley, 2nd Earl of Berkeley 1689–1710For later custodes rotulorum, see Lord Lieutenant of Gloucestershire.Custos Rotulorum of Surrey
This is a list of people who have served as Custos Rotulorum of Surrey.
Sir Thomas Pope bef. 1544–1559
William Howard, 1st Baron Howard of Effingham bef. 1562–1573
Edward Clinton, 1st Earl of Lincoln 1573–1585
Charles Howard, 1st Earl of Nottingham 1585–1618
Sir Edward Howard 1618–1620
Sir Francis Howard 1620 – aft. 1621
Thomas Howard, 21st Earl of Arundel 1624–1636
Henry Howard, Baron Maltravers 1636–1646
John Mordaunt, 1st Viscount Mordaunt 1660–1675
George Berkeley, 1st Earl of Berkeley 1675–1689
Henry Howard, 7th Duke of Norfolk 1689
George Berkeley, 1st Earl of Berkeley 1689–1698
Charles Berkeley, 2nd Earl of Berkeley 1699–1710
James Berkeley, 3rd Earl of Berkeley 1710–1736
Thomas Onslow, 2nd Baron Onslow 1737–1740For later custodes rotulorum, see Lord Lieutenant of Surrey.Geoffrey Warnock
Sir Geoffrey James Warnock (16 August 1923 – 8 October 1995) was a philosopher and Vice-Chancellor of Oxford University. Before his knighthood (in the 1986 New Year Honours), he was commonly known as G. J. Warnock.George Berkeley, 1st Earl of Berkeley
George Berkeley, 1st Earl of Berkeley PC FRS (1628 – 10 October 1698) was an English merchant and politician who sat in the House of Commons from 1654 until 1658 when he succeeded to the peerage.George Berkeley, 8th Baron Berkeley
George Berkeley, 8th Baron Berkeley (1601 – 10 August 1658) was a seventeenth-century English nobleman and a prominent patron of literature in his generation.George Berkeley (British Army officer)
General Sir George Henry Frederick Berkeley KCB (9 July 1785 – 25 September 1857) was a British Army officer and Conservative politician.George Berkeley (died 1746)
The Honourable George Berkeley (1693? – 29 October 1746) was a British politician who sat in the House of Commons for 26 years from 1720 to 1746.Jonathan Dancy
Jonathan Peter Dancy, FBA (born 8 May 1946) is a British philosopher, who has written on ethics and epistemology. He is currently Professor of Philosophy at University of Texas at Austin and Research Professor at the University of Reading. He taught previously for many years at the University of Keele.List of epistemologists
This is a list of epistemologists, that is, people who theorize about the nature of knowledge, belief formation and the nature of justification.Objective idealism
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 (the founder of American idealism), 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.Roman Ingarden
Roman Witold Ingarden (; February 5, 1893 – June 14, 1970) was a Polish philosopher who worked in phenomenology, ontology and aesthetics.
Before World War II, Ingarden published his works mainly in the German language. During the war, he switched to Polish, and as a result his major works in ontology went largely unnoticed by the wider world philosophical community.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.Subjectivism
Subjectivism is the doctrine that "our own mental activity is the only unquestionable fact of our experience", instead of shared or communal, and that there is no external or objective truth.
The success of this position is historically attributed to Descartes and his methodic doubt. Subjectivism accords primacy to subjective experience as fundamental of all measure and law. In extreme forms like Solipsism, it may hold that the nature and existence of every object depends solely on someone's subjective awareness of it. One may consider the qualified empiricism of George Berkeley in this context, given his reliance on God as the prime mover of human perception. Thus, subjectivism.The Analyst
The Analyst, subtitled "A DISCOURSE Addressed to an Infidel MATHEMATICIAN. WHEREIN It is examined whether the Object, Principles, and Inferences of the modern Analysis are more distinctly conceived, or more evidently deduced, than Religious Mysteries and Points of Faith", is a book published by George Berkeley in 1734. The "infidel mathematician" is believed to have been Edmond Halley, though others have speculated Sir Isaac Newton was intended. See (Burton 1997, 477).Unobservable
An unobservable (also called impalpable) is an entity whose existence, nature, properties, qualities or relations are not directly observable by humans. In philosophy of science, typical examples of "unobservables" are the force of gravity, causation and beliefs or desires.However, some philosophers (George Berkeley for example) also characterize all objects—trees, tables, other minds, microorganisms, every thing to which humans ascribe as the thing causing their perception—as unobservable.
"Unobservables" is a reference similar to Immanuel Kant's distinction between noumena (things-in-themselves, i.e., raw things in their necessarily unknowable state, before they pass through the formalizing apparatus of the senses and the mind in order to become perceived objects) and phenomena (the perceived object). According to Kant, humans can never know noumena; all that humans know is the phenomena. Kant's distinction is similar to John Locke's distinction between primary and secondary qualities. Secondary qualities are what humans perceive such as redness, chirping, heat, mustiness or sweetness. Primary qualities would be the actual qualities of the things themselves which give rise to the secondary qualities which humans perceive.
The ontological nature and epistemological issues concerning unobservables is a central topic in philosophy of science. The notion that a given unobservable exists is referred to as scientific realism, in contrast to instrumentalism, the notion that unobservables such as atoms are useful models but don't necessarily exist.
W. V. Metcalf distinguishes three kinds of unobservables. One is the logically unobservable, which involves a contradiction. An example would be a length which is both longer and shorter than a given length. The second is the practically unobservable, that which we can conceive of as observable by the known sense-faculties of man but we are prevented from observing by practical difficulties. The third kind is the physically unobservable, that which can never be observed by any existing sense-faculties of man.