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Is it all just an illusion?

Have you ever wondered whether the world as we perceive it really exists? Is it all just a dream? These questions have been with us since the beginnings of philosophy, but acquired particular force in the 18th century when they were addressed by Ireland’s most famous philosopher and Trinity graduate, George Berkeley. His theory that there are no material things existing outside of our thoughts has been the inspiration behind numerous films and books, including the work of the Argentine short-story writer and essayist, Jorge Luis Borges.

Professor Samuel Rickless, recent Visiting Fellow at the Trinity Long Room Hub in collaboration with the Department of Philosophy, discusses one of philosophy’s most challenging ideas.

George BerkeleyWhy Berkeley?

‘Berkeley is probably the most famous Irish philosopher – and justly so’. Prof Rickless, who has authored three books, including Berkeley’s Argument for Idealism in 2013, points out that Berkeley’s particular position in philosophy is studied by students the world over. ‘The position he holds is that everything that we perceive apart from other minds, is in our own minds. The office we are now sitting in, the sun, the moon, the stars, the earth – they’re all just collections of ideas in people’s minds. That thesis is responsible for countless movies, books, fictional accounts, poems – ever since he came up with this idea, it’s become part of popular culture’. Berkeley’s idealism continues to have a significant influence on the study of philosophy and more generally on our way of looking at the world around us. ‘There is no easier philosopher to use as a way to grab students philosophically than Berkeley. We’ve all had the idea that maybe the outside world is all just a dream – that the existence of things “out there” is just an illusion. You don’t need Berkeley to be gripped by this – even as children we’ve all had this thought.’

Berkeley, Prof Rickless says, is ‘the type of philosopher we would all like to refute, but haven’t been able to do so. This has left us in a kind of uncomfortable position, because on the one hand we’d like to think there is a material world outside our minds and on the other hand when Berkeley comes along and (in just a few words) manages to convince us otherwise in a way that makes it very difficult to see why he might be wrong – we’re hooked. It was one of the reasons I continued to pursue philosophy.’

Berkeley the Man

Berkeley was born in Kilkenny in 1685 and he was raised in Ireland. At the young age of 15, he enrolled in Trinity College Dublin, where he was educated. ‘He was a little bit younger than most students today but he soon distinguished himself as a scholar and stayed on as a Fellow.’ The accomplished philosopher was in his early 20s when he wrote some of his most important works, the works that all philosophy students now read. Berkeley was ordained as an Anglican priest in 1710, and would go on to serve the Anglican Church for the rest of his life. He was made the Bishop of Cloyne in 1734.

‘Before he became a Bishop he was worried that there was a strong chance that society in Britain and Ireland would crumble. There was famine in Ireland and overall it was a very difficult time economically. At the very same time, there were ‘free thinkers’ around who were casting aspersions on religion.  There were libertines, there was gaming, the demand for freedoms suggested that the power of the church should be minimised while he thought the Church was needed as the sort of cement to society and if you lost religion then you would lose morality and eventually end up in civil war and chaos.’ Outlining Berkeley’s many endeavours to appeal to public sentiment in this regard Prof Rickless observes that ‘he published essays in the Guardian when he went to London, he wrote letters, he published works that suggested that we should keep religion, but eventually he thought that the best way of saving civilisation would be to take protestant Christianity to the New World. He was going to save the souls of planters, Indians and anyone else in the colonies who would be receptive to the word of God.’

Berkeley travelled to the New World and ended up in Newport, Rhode Island, which was in those days sparsely populated with settlers. He had the idea of establishing a college in Bermuda, towards which he received a charter from King George I, and a contingent Parliamentary grant for £20,000. However the money never arrived and eventually he was forced to come back to Ireland. ‘He was the most famous intellectual to visit the colonies. He built a house which is still there to this day.  He gave books to Harvard and Yale, helping them start their libraries. I can’t tell you how important he was for the development of early American education and early American philosophy.’

Samuel RicklessBerkeley on Religion

During his fellowship at the Trinity Long Room Hub, Prof Rickless delivered a public lecture in collaboration with the Department of Philosophy entitled 'Berkeley’s Argument for Idealism'.  Prof Rickless was keen to assert that Berkeley’s argument for idealism is independent of Berkeley’s theology. ‘If the argument is right, God might or might not exist and yet we would still be forced to accept that there aren’t any material objects outside our minds.’ Like most philosophers of that time, Berkeley was a theist who thought he could prove that God exists. He also believed that by introducing God he could solve otherwise serious problems facing the theory; ‘How does it come to be that we experience the world in such similar ways? Another question that arises is: how does it come to be that the world is as stable as it is?’

Prof Rickless explains Berkeley’s explanation of why, if all objects are just in our minds, we perceive them in a similar manner: ‘If both of us were looking at a telephone and if you were to describe it to me and I were to describe it to you, we would use very similar words to describe it – its colour, its shape, its size – all of those things would be very similar. How so? Well, Berkeley’s opponents - the materialists - who think that the telephone is a material substance existing outside our mind, will say that it’s obvious why we agree or why we have very similar ways of describing it; it’s because there is one thing that we’re looking at and it has a set of stable properties and we’re both responding to those properties with our sense organs. Berkeley thinks that all of these properties are really just ideas given to us by God.  The reason why we have similar ideas is that God wants us to have similar ideas even though there aren’t any objects outside our minds causing the ideas in our minds. God is a spirit, an infinite spirit. And each one of us is a finite spirit.’

Berkeley’s religious views motivate his solution to the societal problems which prevailed during in the first part of the 18th century. ‘This was a difficult time, here he is, an Anglican Protestant Bishop, and he’s employing loads of Catholic people. He’s trying to make life better for the Irish and he writes a number of economic tracts trying to explain how it is that you can get achieve prosperity. But he thinks the twin evils are scepticism and atheism. And if we could only get people to turn to protestant Christianity – or if we could get them reading the Bible and revere religion – things would be better. He’s worried that if the philosophers and intellectuals of his time (the materialists) are to be believed, we will become sceptical about the existence of an external world.’

Listen to Professor Rickless' recent lecture at the Trinity Long Room Hub:


The Study of Philosophy

Philosophy makes significant connections with other disciplines, including psychology and political theory. Prof Rickless spent his recent fellowship at Trinity exploring Berkeley’s relationship with his contemporaries and looking at his moral and political philosophy. ‘Berkeley wrote a series of sermons that he eventually published as a tract called ‘Passive Obedience’, in which he tried to prove that we should always obey the sovereign, we should never rebel against any civil authority. Something I have come to realise is that, in his view, this doesn’t mean that you should never engage in what we might think of as ‘civil disobedience’; but ‘civil disobedience’ means refusing to follow the law but also accepting the punishment that comes along with it.’

John Locke, the English philosopher, had a major impact on Berkeley, although Berkeley subsequently took a completely opposing view to that of Locke’s take on legitimate authority and the social contract. Prof Rickless is interested in ‘how it is that Berkeley and Locke end up so diametrically opposed – one of them thinking that we should always obey the sovereign whereas the other one thinks that there are going to be some circumstances in which disobedience is justified.’

Prof Rickless is also looking at Berkeley’s engagement with other contemporaries of his time, including Bernard Mandeville and Anthony Ashley Cooper, Third Earl of Shaftesbury. The ongoing relevance of these debates is apparent. Mandeville, to Berkeley’s horror, argues that society benefits as a result of the presence of vices: ‘Mandeville argues that the more people drink, the more needs to be produced. In order to produce drink you have to hire people, and if you hire people you have to pay them. There are huge economic benefits to drunkenness.’ Berkeley engages with Shaftesbury as a result of their differing views on the role of religion: ‘The basic idea that Shaftesbury wants to push is that you can be a good person even if you’re an atheist. Part of the reason for this is that Shaftesbury is worried about the reasons we might have for doing the right thing. Shaftesbury’s thesis is that ‘if you’re doing the right thing only because you’re afraid of what God would do to you if you did the wrong thing – you’re afraid of Hell or you’re afraid of not being immortal, and not getting into Heaven – then you’re not really a good person. You’re not a virtuous person – not doing the right thing for the right reasons. Shaftesbury says people can be virtuous without being religious.’

While students continue to be captivated by Berkeley’s ideas, Prof Rickless discusses the broader importance of philosophy as a discipline in our everyday lives. ‘It’s thanks to Berkeley that we have this sense of vertiginous discomfort about the world – philosophers bring that to life, we have so many worldly cares, but it is still so interesting to have philosophers walking around helping us to make sense of it all. We now just take for granted that there is a world outside our minds – we don’t even think about it. But we should.’


Prof Samuel C. Rickless is professor of philosophy at the University of California, San Diego.  He works in several philosophical subfields, primarily early modern Western European philosophy (with special attention to the work of John Locke and George Berkeley), Ancient Greek philosophy (primarily Plato), ethics, philosophy of law and philosophy of language.  He has authored three books (Plato’s Forms in Transition, 2007; Berkeley’s Argument for Idealism, 2013; and Locke, 2014), and over forty articles on a wide range of topics.

Contact: Aoife King, Communications Officer | Trinity Long Room Hub | | 01 896 3895