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.
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, 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.
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.
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).
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.
The tract A Discourse on Passive Obedience (1712) is considered Berkeley's major contribution to moral and political philosophy.
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 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.
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.
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.
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.
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. In 1734, he was appointed Bishop of Cloyne in Ireland, a position he was to hold until his death. Soon afterwards, he published Alciphron, or The Minute Philosopher, directed against both Shaftesbury and Bernard de Mandeville; and in 1735–37 The Querist.
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.
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.
"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 University of California, Berkeley, was named after him, although the pronunciation has evolved to suit American English: (// 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."
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.
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 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 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
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."
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 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 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’s argument hinges upon an omniscient, omnipresent deity.