George Berkeley (1685 - 1753), Ireland's most famous philosopher¹, was possibly also the world's greatest philosopher-bishop since St Augustine. His contribution to philosophy was radical, and he seems to have relished his own reputation as the holder of outrageous opinions. In his book Three Dialogues, his mouthpiece Philonous is accused by his doubtful friend Hylas of being 'one who maintained the most extravagant opinion that ever entered into the mind of man.' By the end of the three dialogues Philonous has of course enlisted the doubting Hylas as a firm supporter. Berkeley's contemporaries were not so easily convinced, but he did have a powerful effect on the later philosopher David Hume, who in turn influenced Immanuel Kant. Kant never quite digested or accepted Berkeley's point, however, and though he made the mind responsible for the categorisation of things, by which means they are perceived, he felt obliged to elaborate a theory of the 'Thing-in-itself', which is just what Berkeley denied.

In the following century Arthur Schopenhauer used Berkeley's insight as the basis for his concept of The World as Will and Idea. Unfortunately he couldn't go the whole way either, and simply said, without demonstrating it, that Berkeley could not be right.

Berkeley's Extravagant Opinion

The main point of Berkeley's philosophy is that there is no such thing as matter. It doesn't exist². There are only minds, and ideas that occur in those minds. All the things we perceive are ideas; the fact that we perceive them means that we are ourselves essentially minds.

Berkeley dared to question Sir Isaac Newton on his mathematics, particularly infinitesimals. He was himself an able and subtle mathematician; but he insisted that nothing in the real world could be divided infinitely. He also challenged Newton's notions that space and time could be said to exist on their own without anything happening in them. Time, said Berkeley, does not 'flow equably' regardless of its contents; time is the succession of ideas in the mind.

The Freethinker

How he arrived at his immaterialism is perhaps plain enough to see. He started out as a constantly-questioning youngster, as he tells us in his private notebook³: he was 'distrustful at eight years old'. The fashionable attitude for young bucks at the beginning of the 18th Century was the adoption of a thoroughgoing radicalism called 'Freethinking', which challenged all accepted wisdom, and religion in particular.

The young Berkeley seems to have applied the method of freethinking to everything he came across. When he studied philosophy at Trinity College Dublin, the new and exciting textbook was John Locke's Essay Concerning Human Understanding, and in it Berkeley's eagle eye fell on a decidedly dodgy description of substance⁴. This is defined as something which we suppose to underlie all the perceptible features of things, though substance is not in itself perceptible, according to Locke⁵.

Applying to Substance the scepticism the Freethinkers applied to God, Berkeley concluded that this mysterious matter is something which makes no appearance in the world, and which we can do perfectly well without. Logically, to say that we cannot imagine doing without something is not sufficient to prove that such a thing is present⁶. Indeed, by Occam's Razor⁷ we are bound to discredit such an imaginary entity.

We are left then with nothing but our perceptions; but the evident fact that our perceptions are well-knit and coherent in daily life amounted, for Berkeley, to nothing short of the divine. In this way his scepticism, followed unflinchingly to its conclusion, brought him back to religion. Nothing essentially inaccessible to mind can be presumed to exist: Berkeley's motto became esse est percipi - 'to be is to be perceived'. We are not, however, isolated minds; we rely on shared experience in the greatest and least things in life. The ground of our unity, the universal mind within which we commonly perceive, act and communicate, he concluded, is God.

Berkeley accordingly became an advocate of religion; he took holy orders, as was required of those lecturing at Trinity College. He lectured in Greek, Hebrew and Divinity, becoming a Fellow of the College in his early twenties. It may seem in hindsight a large step for Berkeley to decide that the Source Of All is identical with the Holy Trinity as worshipped in the Church of Ireland, and to go all the way to becoming a bishop of that church; but he took that path, and it certainly helped him achieve a good deal in his lifetime.

Vanessa and the American Venture

Berkeley must have been a most engaging and persuasive person. He became acquainted with Alexander Pope in London, who described him as possessing 'every virtue under heaven'⁸ - extraordinary praise from such a sharp satirist. He was also friends with Jonathan Swift, who called him 'an absolute philosopher', in the sense of one who does what is right rather than what is gratifying or convenient. Swift had a wealthy lover, Esther Vanhomrigh, whose story he told in the poem Cadenus and Vanessa⁹. When Esther died she left a very large sum¹⁰ to Berkeley, although she was 'a perfect stranger' to him. Berkeley accepted this money as a godsend and made good use of it. He persuaded the British Government to grant him a further enormous sum, £20,000, to go and found a university in America. Berkeley sailed to New England, where he stayed for over two years. His plan was to build a seminary that would educate not only the European settlers' sons, but also young Native Americans and African slaves, so that they could become ministers and teachers among their own peoples.

On the map, Bermuda seemed the ideal place for this. So much the worse for those who trust maps, as Berkeley realised when he arrived in New England; Bermuda was utterly impractical for many reasons. By that time it was impossible to alter the terms of his government grant, which in any case never came through¹¹, so he endowed existing colleges instead. On leaving America, Berkeley sent Harvard and Yale boxes of books, enriching their libraries. He also gave Yale a farm to support the college, which was at the time a struggling rural seminary with thirty or forty students.

When Berkeley was in America (1728 - 31), he was the most famous person ever to have travelled there: his books had been published in London and he was a dean of the (Anglican) Church of Ireland. At that time, to be a bishop, or even a dean, was no small matter; it was a position of influence perhaps comparable to that of a present-day senior executive of a major corporation.

Berkeley enlisted at least one effective disciple there, the American Samuel Johnson, who consulted him and followed Berkeley's plan in setting up what is now Columbia University¹². The University of Pennsylvania also acknowledges his influence, as does the Berkeley Divinity School at Newhaven.

There are now many towns in the USA named after George Berkeley, including the home of the University of California. These were so named, probably not so much in recognition of his philosophy, or his philanthropy, as for a stirring poem he wrote whose last verse begins 'Westward the course of Empire takes its way.'

It's All In Your Head

Berkeley's American friend Samuel Johnson is not to be confused with his namesake, the English lexicographer, who made an impatient attempt at refuting Berkeley's immaterialism. He kicked a rock, so that his foot rebounded off it, to show that it contained matter; but in that act he only showed his failure to grasp what Berkeley's theory said. It has been misunderstood fairly consistently ever since, though some philosophers, notably Ludwig Wittgenstein, have found it both logically sound and meaningful. In the Chapel of Trinity College Dublin there is a stained glass window dedicated to George Berkeley, erected a hundred years after his death and furnished with the wry quote: 'And when the multitude heard him, they were astonished at his doctrine' (Matthew 22:32).

To see the world in Berkeley's terms requires a mental change of perspective¹³ such as the following:

• Question: How far away is the Milky Way?

• Hint: The nearest star we see at night, Alpha Centauri, is 4.24 light years away, and it is indeed in the Milky Way. That however is not the right answer.

• Answer: Our own local star the Sun is in the Milky Way, as are we. Therefore the Milky Way is at no distance at all.

Just as our solar system is completely in the galaxy, the physical world we inhabit is completely in perception, that is to say, in the realm of the perceptible.

Something - it could be impatience or reluctance - has consistently prevented people from working out just what is and is not implied by Berkeley's immaterialism. It is perhaps easier to point to what Berkeley did not claim. He did not say that everything is 'in your head'. This makes no sense, since heads are also in the realm of perceptible things. He did not say that things have no solidity; solidity is a perceptible feature. He did not question the reality of the world, as perceived; on the contrary, the obstinate empirical facts of the real world were the grounds of his objection to Newton’s infinitesimals.

Remove matter and the world is left exactly as it was, only without one explanation of what holds it together; an explanation which Berkeley found to be both unnecessary and insufficient. One consequence to the thinker who takes this step is that the greatest miracles of religion and fable become trivial compared to the single mystery that anything can appear to exist at all.

Berkeley excluded such scientific extensions of perception as telescopes and microscopes from his common-sense world, the world in which we live and make our moral choices; he said that what is seen through the microscope is another world. To this extent he was perhaps anti-scientific; but on the other hand the scientific community has quietly come round to accepting Berkeley's opinion as to the provisional and necessarily falsifiable status of scientific hypotheses.

Common Sense

Berkeley denied the existence of substance, defined as something essentially inert or passive. He allowed only two ways for something to have a claim to existence: either by perceiving, or by being perceived. Locke's inert matter failed on both counts. Without the stimulus of Locke's unfortunate description of substance, Berkeley's argument might not have arisen. The interesting thing, though, is how many problems Berkeley solved with this stroke¹⁴ - too many, for his contemporaries. Transubstantiation, for one, simply ceases to be an issue. Berkeley's stance was ecumenical, as shown in his most successful publication, A Word to the Wise (1749). Addressed to the bishops and clergy of the Roman Catholic Church, it urged them to take steps to improve the circumstances of the Irish poor, by encouraging industry and self-esteem. His words were direct and forceful, yet so tactfully chosen that the Roman Catholic bishops and clergy responded with an enthusiastic endorsement.

In his later life, as Bishop of Cloyne in County Cork, Berkeley became a practical and energetic promoter of the Irish people's wellbeing. He wrote The Querist, a challenging and ingenious tract on economics¹⁵ and became famous as a healer of many various ills, using a purgative potion whose recipe he may have learnt from the Native Americans: tar water. This became such a fad that an apothecary in late 18th-Century London, when asked if he sold tar water, is said to have replied that 'he sold nothing else'.

Further Reading

• A list of further works on George Berkeley
• For a serious look at the subject, try the Philosophy Pages or The Internet Encyclopedia of Philosophy
• Squashed Philosophers - a history of Western thought for those with short attention spans
• Applied thinking - How to Be a Philosopher