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I. How Morpheus Sees Reality

“What is real? How do you define ‘real’? If you’re talking about what you can feel, what you can smell, what you can taste and see, then real is simply electrical signals interpreted by your brain.”
Morpheus, The Matrix

Despite this rather opaque comment, Morpheus actually relies on a pretty straightforward understanding of what it is that makes something real as opposed to unreal. He relies on this understanding when he classifies his hovercraft, the Nebuchadnezzar; deserted and devastated cities on the surface of the Earth; and the populous and thriving (at least until the end of the second film) city of Zion near its centre as real. And he relies on it when he classifies the world of the Matrix; what he calls ‘the Construct’, the white world in which he first explains the nature of the Matrix to Neo; and the virtual arena in which they first spar as unreal. He relies on it to make sense of his general mission as being to wake people up from unreality and into reality. And he relies on it to make sense of his particular mission as being to do this for Neo, the person whom he believes will be able to destroy the unreality of the Matrix for good. In so relying on it, Morpheus actually assumes that there’s an important difference between those electrical signals that are fed into our brains by computers when we’re floating in our tanks and those that he has when, for example, he’s sitting with his crew in the cockpit of the Nebuchadnezzar. If Morpheus thought that reality was simply a matter of having electrical signals interpreted by your brain (however these signals got there and however little the interpretations we gave them resembled anything outside themselves), then he’d think that people were just as much in touch with reality when they were floating in their tanks as he was when he was sitting in the cockpit of the Nebuchadnezzar. In both cases, there are electrical signals being interpreted by brains. Yet of course Morpheus doesn’t think that the experiences people have in their tanks are putting them in touch with reality, whereas he does think that the experiences he’s having as he sits in the cockpit of the Nebuchadnezzar are putting him in touch with reality. So he can’t believe that reality is simply a matter of having electrical signals interpreted by your brain; he must believe something else. In fact, he believes what the rest of us believe. What’s this?

To put it simply, Morpheus believes that the real is that which exists exterior to our minds; the unreal, by contrast, is that which exists only in our minds. This is the understanding which guides him in classifying, for example, the cockpit of the Nebuchadnezzar as real and the world of the Construct as unreal. He thinks that his ship is there even when nobody’s experiencing it; he doesn’t think that the television he shows Neo in the Construct is there even when nobody’s experiencing it, when nobody is ‘loaded up’ into that particular virtual world. The Nebuchadnezzar exists in its own right, independently of our ideas about it. It’s real. The television exists only in the minds of those suitably ‘loaded up’. It’s unreal. We share with Morpheus the assumption that reality is a matter of being part of the mind-independent world, which is just as well. Otherwise, we’d never understand what was going on in the films. We’d never understand what the difference was between being in the Matrix and being out of it. We’d never understand what it was Morpheus was trying to do. We wouldn’t enjoy the films at all. What other assumptions about reality do we share with Morpheus?

As he shows in the passage quoted above, Morpheus assumes that the real world causes things to happen in our bodies, happenings that give rise to electrical signals that are ultimately interpreted by our brains, thus forming our ideas about that world. He assumes that this process occurs whether or not we’re in the Matrix. If we’re in the Matrix, then the world is causing things to happen in our bodies via a system of pipes fed into our nervous system; it’s the signals coming down these pipes that find their way into our brains for interpretation. If we’re in the real world, then the world is causing things to happen in our bodies via light landing on our eyes; sound waves reaching our ears; and so on. It’s the signals caused by these changes that find their way into our brains for interpretation. Why is it that we – with Morpheus – think that in the one case these signals are putting us in touch with reality and in the other case they’re not? What’s the important difference between signals finding their way into our bodies in one way and their finding their way into our bodies in the other?

It’s not obvious how Morpheus would answer this question. So far – I’ve only seen the first two films – he hasn’t addressed it. That’s not his fault: as you know if you’ve seen the films, he’s been kept quite busy with other things. Philosophers have characteristically had more time (and less agents) on their hands. Thus they’ve pondered it a bit more. One answer has appealed to many philosophers over the ages. It’s this: these signals are putting us in touch with reality only if the ideas that they give rise to resemble the things that cause them; if the ideas these signals give rise to do not resemble the things that cause them, then they’re not putting us in touch with reality. For example, if the signal, which, once interpreted, becomes Morpheus’s idea that ‘the control-board of the Nebuchadnezzar is just in front of me’ is caused in him by the control-board of the Nebuchadnezzar’s being just in front of him, then this idea resembles the thing that’s causing it and thus is putting him in touch with reality. On the other hand, if the signal which, once interpreted, becomes his idea that ‘there’s a television just in front of me’ is not caused in him by a television that’s just in front of him, but is in fact caused in him by an unimaginably complex computer, then it doesn’t resemble the thing that’s causing it and thus is not putting him in touch with reality. This seems like a pretty straightforward understanding of what it is that makes an idea put us in touch with reality. I’m going to assume that Morpheus and we share this understanding too.

Unless we seriously consider the possibility that we might be in the Matrix or some such, we won’t find reason to question a comforting view that we will then think of ourselves as basing on these assumptions. The comforting view I have in mind is the view that almost all of our ideas pretty closely resemble the objects that cause them; thus they do put us in touch with reality. Consider, for example, your idea of the page in front of you from which you take yourself to be reading this. (I’m assuming that you’ve got a hardcopy of this, rather than are just reading it off the website.) Your idea of this page represents it as having certain qualities – a particular shape, size, colour, and so on – and you have the comforting belief that the thing which is causing this idea in you resembles your idea in having these qualities. You believe that there really is a page with the shape, size, colour, and so on that your idea suggests. You believe that it’s this page reflecting light of certain wavelengths – light which lands on your eyes, giving rise to electrical signals that are ultimately interpreted by your brain – that forms your idea of it, an idea which thus resembles its cause. You don’t believe that your idea of the page is caused in you by signals originating from something entirely different from a page – an unimaginably complex computer, for example. If it were, then your idea of the page wouldn’t resemble the thing that was causing it at all, and then it wouldn’t be putting you in touch with reality at all. I suggest that we hold this comforting view of the way our ideas get into our heads for the vast majority of our ideas. What’s comforting about it is that it’s the view that we’re basically in touch with reality; we’re not in an inescapable illusion.

Only very rarely do we think that we might have an idea of an object that’s caused in us by something that’s not very much like the idea it causes. Maybe you’ve been to a magic show where, during his act, the magician made a ghostlike form appear in a puff of smoke and then – apparently – float in thin air just ahead of you. Initially perhaps you thought that there really was such a being, but, on reflection, you probably decided that your idea as it had been caused in you did not in fact resemble what was out there doing the causing. You decided that there was probably not in reality an ethereal floating figure, causing an idea in you that resembled it. Rather, you concluded that there was a mannequin hanging on a wire causing an idea of an ethereal floating figure in you, an idea of yours which thus didn’t closely resemble reality at all. But such occasions are infrequent. Unless we seriously consider the possibility that we are in the Matrix or some such, we will hold the comforting thought that veridical experiences are the norm, illusory ones the rare exceptions.

But, if we once seriously consider the possibility that we’re in the Matrix or some such, this comforting thought is threatened. If you’re in the Matrix, then you’ve never had a veridical experience in your life; rather than illusions being rare exceptions, illusions are the norm. If you’re in the Matrix, then the idea you have of the page from which you currently take yourself to be reading, for example, is not in fact caused in you by a page at all – by an object which resembles your idea of it pretty closely. An unimaginably complex computer causes it in you. So your idea doesn’t resemble its cause. So it’s not putting you in touch with reality. What goes for your idea of the page goes for your ideas of everything else you take yourself to have encountered. If you’re in the Matrix, then all the objects you take to exist exterior to your mind don’t really exist at all. Your ideas of them – the ‘electrical signals interpreted by your brain’ as Morpheus might put it – are still there, but the things they’re ideas of aren’t there; they’re not real. You’re living in an inescapable illusion.

The worry that all our ideas about the world might be mistaken only makes sense on the assumption that we share with Morpheus that reality is independent of our ideas about it and thus that there’s something outside themselves by reference to which our ideas may go wrong. Only on this assumption does it make sense to worry that our ideas about reality might go wrong by failing to resemble the things that cause them. But, having made the assumption that there’s a mind-independent reality on the one hand and our ideas about it on the other, the worry that the latter might not resemble the former is rationally inescapable for anyone who thinks through the assumption’s implications. To be in a position from which we could have reasons to remove the worry, we’d have to be able to do the following: climb outside our own minds and perceive reality on the one hand and our ideas about it on the other. Then we could compare the two and see whether or not the latter resembled the former. If we could climb to such a position, we could then say something like, ‘I see the world as it exists independently of my perception of it over there and I see my ideas about the world over there; and, comparing them, I see that they resemble one another’. But we can never climb outside our own minds, see things from a point of view that’s not our own. We must always look at the world through the spectacles of our ideas of it. So we can never justify our predilection for adopting the comforting view that most of our ideas resemble the mind-independent things that cause them, rather than the worrying Matrix alternative, that they don’t. Once we think about the assumptions that I’ve suggested we share with Morpheus, we realise that we can never know whether or not we’re in the real world or an unreal world. And we shouldn’t think that Morpheus is any better off than we are in this regard. For perhaps Morpheus has never in fact sat in the cockpit of the Nebuchadnezzar and looked at its control-board, for perhaps the Nebuchadnezzar doesn’t exist. Perhaps it’s a computer simulation too. How could he know?

Just as you can have plays within plays, so you can have virtual realities within virtual realities. Perhaps, even when he thinks he’s sitting in the cockpit of the Nebuchadnezzar, Morpheus is still in a virtual reality world; it’s just a virtual reality within a virtual reality; or perhaps it’s a virtual reality within a virtual reality, within a virtual reality. In any case, Morpheus, Neo, Trinity, and the rest should conclude that whatever experiences they seem to have, they can’t know they’ve escaped from the Matrix. For all they know, they might each still be floating in their tanks being fed illusory experiences to make them think that they’ve got out of their tanks; met up with one another; and are – at last – in touch with the real world. If you were the ‘Architect’, wouldn’t this be the sort of trick you’d play on them?

II. How Berkeley Sees Reality

It is indeed an opinion strangely prevailing amongst men, that houses, mountains, rivers, and in a word all sensible objects have an existence natural or real, distinct from their being perceived by the understanding. But with how great an assurance and acquiescence soever this principle may be entertained in the world; yet whoever shall find in his heart to call it in question, may, if I mistake not, perceive it to involve a manifest contradiction.
Berkeley

George Berkeley was an Irish Philosopher. Born in 1685, he is most famous for works written whilst he was still in his twenties: – An Essay Towards a New Theory of Vision (1709); A Treatise Concerning the Principles of Human Knowledge (1710) and Three Dialogues Between Hylas and Philonous (1713). After writing these works, he travelled widely in Europe and America and had been made a bishop (of Cloyne, a diocese in southern Ireland) before he died in Oxford in 1753.

Berkeley’s Philosophy might seem to offer us a radical solution to the problem that we were left with at the end of the previous section. To appreciate how this solution might work, it’ll help if we go back over why it is we found ourselves with the problem. It was a problem that was generated for us by the way of looking at things that I suggested that we shared with Morpheus. I suggested in the previous section that we believe, with Morpheus, that there’s some mind-independent reality out there that’s causing our ideas and that our ideas could in principle resemble. And I suggested that we believe that if and only if our ideas do in fact resemble the things in this mind-independent reality that cause them do they put us in touch with this reality. If they don’t, they’re illusions. This way of looking at things enabled us to understand the division between the reality of the world of the Nebuchadnezzar and the unreality of the world of the Matrix. When Morpheus sits in the cockpit of the Nebuchadnezzar, his ideas are formed in him by things that they resemble; he’s in touch with reality. (This is assuming of course that this isn’t actually a virtual reality within a virtual reality.) When he’s loaded up into the Matrix, his ideas are formed in him by things that they don’t resemble at all; he’s entered the world of illusion. This way of looking at things generated an insurmountable problem for him and us: how can we know if any of our ideas do in fact resemble the things that cause them? How can Morpheus know that the Nebuchadnezzar isn’t a virtual reality within a virtual reality? We can’t and he can’t, because no one can ever see the world except through the spectacles of their ideas about it. And if we can’t know that, then – because it’s resemblance between our ideas and reality that makes our ideas put us in touch with reality – we can’t know whether or not we’ve ever been in touch with the real world at all. We’ll have to conclude that, for all we know, we could be living in a permanent illusion. We’ll have to conclude that Morpheus can’t be justified in thinking that the Nebuchadnezzar isn’t a virtual reality within a virtual reality. What to do?

Berkeley’s Philosophy seems to offer us an answer to this problem because it rejects one part of the theory that generates it. Berkeley’s Philosophy is most famous for something it denies: it denies that there is a mind-independent world. Berkeley’s solution to the problem we’re facing then wouldn’t be so much a solution to the problem as a dissolution of the way of thinking that leads to it. As a way of sketching the outlines of his position, let’s look at a couple of the arguments that lead Berkeley to adopt it.

One of the arguments that takes Berkeley to his radical position is this: We believe that ideas can in principle resemble things in the real world. For example, Morpheus believes that his idea of the cockpit of the Nebuchadnezzar resembles the cockpit of the Nebuchadnezzar; thus, he believes, it puts him in touch with reality. But if Morpheus is right about the nature of ideas, then his idea of the cockpit of the Nebuchadnezzar is just an electrical signal interpreted by his brain and an electrical signal in his brain doesn’t resemble a small room with chairs that can be used to control a hovercraft at all. It resembles, well, just other electrical signals in his brain and electrical signals in the brains of others. Ideas, it seems, cannot actually resemble anything other than ideas. But if it’s only by resembling a thing that an idea can manage to put us in touch with that thing, it follows that we cannot have ideas about anything other than ideas. All we can ever think about, or thus make reference to in our metaphysical theories, are ideas. So, if we think that ideas can only get to be of the real world by resembling things in the real world, then we should conclude that, because ideas can’t resemble anything except other ideas, the real world must just be a construction built out of our ideas. Berkeley’s Philosophy is thus often called ‘Idealism’; there’s no mind-independent world, there’s just ideas. As Berkeley puts it, ‘it is impossible for me to conceive in my thoughts any sensible thing or object distinct from the sensation or perception of it’ and so any alternative to Idealism is, quite literally, inconceivable. The truth of Idealism is, according to Berkeley, ‘so near and obvious to the mind, that a man need only open his eyes to see’ it. Berkeley takes Morpheus’s question, ‘How do we define ‘real’?’ and gives it a quite different answer from the one that I’ve argued we give it. Rather than saying that the real is just whatever it is that exists independently of our having ideas of it, he says that the real is our ideas. That’s all that ‘real’ can mean. Let’s have a look at another argument he uses for his position.

How else could we define ‘real’ – attach meaning to the term – except by linking it to something in our minds? There’s no way. And what else do we have in our minds but ideas? Nothing. So, if ‘real’ means anything at all, it can only mean some sort of construction of ideas. And once we realise that we must define ‘reality’ as we must define everything else, namely in terms of our ideas, then we realise that we can’t make sense of ‘reality existing independently of our ideas’. To posit that there might be a reality independent of our ideas would be to posit that there might be something that existed even though none of the things we use to define it – our ideas – existed, which is, as Berkeley puts it in the quotation above, ‘a manifest contradiction’. As he goes on, ‘For what are the forementioned objects but the things we perceive by sense, and what do we perceive besides our own ideas or sensations; and is it not plainly repugnant that any one of these or any combination of them should exist unperceived?’

It might thus look as if Berkeley’s Philosophy has solved – or rather dissolved – the problem we were wrestling with at the end of the previous section. Once we’ve got rid of the notion that reality is independent of our ideas, it looks as if we can get rid of the worry that our ideas might go wrong by failing to resemble that mind-independent reality too. It looks as if that worry can no longer makes sense. If Berkeley’s right, it doesn’t make sense to think that one’s ideas might fail to resemble a mind-independent reality because the notion of a mind-independent reality doesn’t make sense – it’s ‘a manifest contradiction’. One might as well worry that one’s ideas might fail to resemble a four-sided triangle. The worry that our ideas might not be putting us in touch with reality was premised on the assumption that reality was something other than our ideas about it and it was only if our ideas resembled it that they put us in touch with it. If reality is just our ideas about it, then of course there’s no way our ideas could fail to resemble reality. So there’s no way our ideas could fail to put us in touch with reality. If we’re all in the Matrix, so what? The page you see is still real because being a real page is just a matter of being a set of page-like ideas and a set of page-like ideas certainly exists. Have a look at the room in which you take yourself to be reading this page. You’ve now got a set of room-like ideas. Well, according to Berkeley, being a real room is just a matter of being such a set of ideas, so the room in which you take yourself to be reading this is real too. Remember the conversation within the Matrix between Cypher and Agent Smith, where Cypher says, holding up a bit of steak on a fork, ‘I know that this steak doesn’t exist.’? Well, he’s wrong. Being a real bit of steak is just being a set of steak-like ideas in someone’s mind and the Matrix is causing a lot of steak-like ideas in Cypher’s mind. No need for you to worry about the Matrix when you think you’re looking at a page or for him to worry about it when he thinks he’s eating a steak then. If it seems real, it is real. This page seems real; this page is real. The steak seems real; the steak is real. You and he can return to the comforting view that your ideas are putting you in touch with reality because you now know that reality is just a matter of your ideas about it. Enough said? Sadly not.

Berkeley doesn’t actually think that something’s seeming to you to be real is sufficient to make it real. He’d agree with Cypher here and say that the steak is not real. He thinks that ideas can in fact go wrong, not by failing to resemble a mind-independent world (that wouldn’t make sense) but by failing to resemble other ideas. He says this because he wants to allow that there can be illusions. And we’ll want to allow this too. Remember the magic show, where you had an idea of an ethereal floating figure, an idea which you thought on reflection was a skilfully created illusion. The example of the magic show reminds us that we do want to say that sometimes our ideas don’t put us in touch with reality, so we’ll have to have some way of understanding what it is in virtue of which they do and what it is in virtue of which they don’t. It won’t do to say that all ideas are of real things because it’s sufficient for a thing to be real that someone has an idea of it. That’s not sufficient. People have ideas of ghosts and all sorts of other things that aren’t real. So Berkeley’s got to come up with a way of explaining why some ideas don’t manage to be of real things even though reality is just a construction of ideas. He’s lost the ability to explain illusions in terms of ideas failing to resemble things in the mind-independent world because he’s lost the mind-independent world. So what he does is tell us that illusions are illusions not because they fail to resemble a mind-independent reality, but because they fail to resemble other ideas.

Take Macbeth ‘seeing’ the ghost of Banquo seated at the table before him as an example. Berkeley would be first to admit that this ghost is not real. Why? Not because the idea in Macbeth’s mind doesn’t resemble anything out there in the mind-independent world (Berkeley’s just said that to say that wouldn’t make sense). It’s not real because the idea in Macbeth’s mind doesn’t resemble any ideas in other people’s minds. As his guests look on at him raving, none of them can see the figure to whom he points. The idea of Banquo’s bloody form exists only in Macbeth’s mind, not in anyone else’s. Ergo, it’s an illusion. An idea’s putting one in touch with reality is then a matter of the idea resembling ideas in other peoples’ minds. A ‘hallucination’ that everyone could see, taste, smell, touch, and hear would be no hallucination at all – it would be real. A hallucination – however vivid in the mind of the person who has it – that doesn’t resemble ideas in anyone else’s mind, that no one else thinks they can see, taste, smell, touch and hear, would – by contrast – be a genuine hallucination, i.e. an illusion. It looks then as if Berkeley is saying this: objects are just collections of ideas in peoples’ minds; ideas that are shared by more than one person are realities; ideas that only appear in one person’s mind are ‘unrealities’ or illusions.

If this were what he was saying, Berkeley’s Philosophy might still seem to offer some hope of defeating the Matrix worry. If there are millions of people in the Matrix, all having the same ideas, then that’s enough for the things they’re having ideas of to be real things. Remember, on this version of Berkeley, the city we see Morpheus moving around in within the Matrix, let’s say, is just a collection of ideas in people’s minds. The difference between a real city and an unreal city is that a real city is constructed out of ideas that resemble one another and are being had by a number of people greater than one. An unreal city is a construction of ideas in the mind of just one person. If we’re in the Matrix, then there’s a large number of people all having ideas that resemble one another – the Matrix is an interactive virtual environment populated by millions. So, the world of the Matrix is real. The world of the Nebuchadnezzar is real too. Each is a world where there’s a large number of people having ideas that resemble the ideas being had by other people and that’s enough for both worlds to be real.

Obviously, this isn’t the way Morpheus sees things or the way we see things. But it might be rather like the way Cypher comes to see things by the end of the first film. There he has a conversation with Trinity where he disagrees with her about which is the real world. He says that the world of the Matrix ‘can be more real than this world.’ (He’s obviously shifted ground since his discussion with Agent Smith concerning the bit of steak.) Unfortunately, we don’t get to hear too much more about the view to which he’s now been drawn because, before he can tell us and – arguably more importantly – before he can kill Neo, Tank fries him to death with a large electrical discharge (as far as I am aware, the first time a discourse on metaphysics has been so terminated). In any case, we don’t feel too much sympathy for Cypher and one reason – perhaps not the main reason – is that we cling with Morpheus, Trinity and Neo to the view that the world of the Matrix is unreal and the world of the Nebuchadnezzar is real whatever abortive attempts Cypher might make to convince people otherwise. But perhaps we’re wrong to think this way. Perhaps we should be more sympathetic to a Later-Cypher-type view. If reality is just a communal construction of ideas, then we should say that because each world involves a community constructing objects out of ideas, each is equally real. Or, if the size of the community counts, then, because the Matrix construction is a set of ideas being had by more people than the Nebuchadnezzar construction, the Matrix is indeed more real, as the Later Cypher says. But even if we could get ourselves to believe something along these lines, it wouldn’t actually solve the problem we were left with at the end of the first section. Whilst on the view that as long as there’s two or more people having ideas that resemble one another that’s enough for the thing they’re having ideas of to be real, we can know that if our ideas resemble ideas in the mind of someone else, then they’re putting us in touch with reality, we still can’t know whether or not our ideas do resemble ideas in the mind of anyone else. Each one of us might think, ‘Maybe I’m the only one still hooked up to the Matrix, everyone else having got out and having been replaced as I seem to experience them by programmes. If so, then I’m the only one having ideas like mine. Everyone else is having a whole different set of ideas. If so, then – because an illusion is just an idea that doesn’t resemble anyone else’s – as the last one in the Matrix, I’m now in an illusory world.’ The last person out of the Matrix, in virtue of being the odd one out in terms of the ideas he or she happens to be having, will be missing out on reality even if reality is a communal construction out of ideas. Even if we accepted that being real was just a matter of being an idea shared by at least two people, we’d still be left with the problem of how we can know we’re not suffering from an inescapable illusion because we’d still not know whether any idea that we had was in fact shared by anyone else.

In any case, it’s not, according to Berkeley, actually a matter of the number of people having the same ideas. Why’s he think that? Because he wants to allow that you can have an idea of something and that thing be real even if no other human has ever had or will ever have an idea of it. For example, suppose you’re on the main deck of the Nebuchadnezzar one day, looking at the computer screens and sipping on the local home-brew. You notice a previously unobserved speck of dirt on one of the screens; brush it off; and promptly forget all about it. If so, then your idea of this speck of dirt is an idea that doesn’t resemble any idea any other human has ever had or will ever have. Yet still, we’d want to say, your idea is an idea of a real speck of dirt. We don’t want every unique experience to have to be classified as ipso facto an illusory one. So we can’t make the difference between an idea putting you in touch with reality and one not putting you in touch with reality be the difference between an idea resembling one had by other humans and one not resembling any had by other humans. Here Berkeley brings in God – you had to expect that he’d bring God in somewhere; he was a bishop after all. Actually, says Berkeley, your idea of this speck of dirt wouldn’t be a hallucination even if it didn’t resemble an idea had by any other human if it did in fact resemble an idea in God’s mind. So, according to the real Berkeley, getting your ideas in touch with reality is getting your ideas to resemble those in the mind of God. But here again the problem we were left with at the end of the first section resurfaces. There’s no mind-independent reality, but there is a human-mind-independent reality – there are the ideas that exist in the mind of God. And, according to Berkeley, getting your ideas in touch with reality is getting them to resemble these ideas. But how can you ever know that your ideas resemble ideas in the mind of God? Again, to answer the problem one would have to be able to step outside one’s ideas; look at one’s ideas on the one hand and God’s ideas on the other; and then compare them for resemblance. But this is just impossible. Berkeley’s Philosophy doesn’t seem to have got us out of the problem at all.

So, even if you accept with Berkeley that there’s no mind-independent reality because all that’s real is ideas, you’ll still believe that some of these ideas aren’t of real things. And you’ll need to explain how this can happen. If you hold the ‘community construction model’, you’ll think that the ideas that the community accepts are ideas of real things; and that those they don’t accept are ideas of unreal things. But if you go down this road, your problem will become, ‘How do I know if the ideas that I have of the community around me accepting or not accepting my ideas are ideas of the real community rather than of an unreal community?’ If you hold the ‘God model’, you’ll think that it’s the ideas of yours that resemble those in the mind of God that are putting you in touch with reality; and that it’s those that don’t resemble ideas in the mind of God that aren’t. But if you go down this road, your problem will become, ‘How do I know that my idea of God is an idea of a real God rather than an unreal God?’ or – more tellingly – ‘How do I know that my idea of a resemblance between my ideas and those in the mind of God is an idea of a real resemblance rather than an idea of an illusory resemblance?’

Without a mind-independent world, the worry that our ideas might not accurately resemble a mind-independent world can no longer make sense, but it’s a mistake to think that this removes the worry that we were left with at the end of the first section. The same worry resurfaces as the worry that one’s ideas might not sufficiently resemble the ideas in terms of which reality is defined (community opinion or God’s). As soon as we allow the possibility of illusion and explain it in terms of an idea failing to resemble something, we have to allow that, for all we know from looking at our ideas, all of our ideas might be illusions. Is there any way forward?

You’ll recall that Berkeley’s strategy in trying to answer the problem was to deny one part of the theory that generated it. This theory said that there was a mind-independent reality and that our ideas get to put us in touch with it only by resembling the bits of it that are causing them. Berkeley’s implementation of this strategy resulted in him denying the first part of the theory, that there’s a mind independent reality. He didn’t deny the second, that ideas get to put us in touch with this reality by resembling the bits of it that are causing them. In fact, one of his arguments for his position relied on affirming it (his argument that because ideas can only ever resemble other ideas, then all that we can ever think about are ideas; thus, we’ll have to define reality as a construction out of ideas). We’ve seen that his implementation of his strategy didn’t answer the problem. But perhaps the strategy was right. We should deny an element of the theory that generates the problem. We’ve tried denying the mind-independent world part and seen that that’s not going to get us anywhere. Perhaps then we should deny the other part, the part that says that our ideas get to be about this world by resembling the bits of it that are causing them. Perhaps we should replace this account with another.

What would this other account look like? Well, let’s just get rid of the resemblance bit of the account that we’ve been assuming hitherto. Let’s say that our ideas of things get to be about the things they’re about not by resembling whatever it is that causes them but just by being caused by whatever it is that regularly causes ideas of the relevant sort. This account of what makes an idea refer to things had arguably already been canvassed when Berkeley was but a toddler, by an English Philosopher called John Locke, someone by whom Berkeley was very influenced (albeit almost always to disagree). In his Essay (full title: An Essay Concerning Human Understanding), Locke says that ‘simple ideas, which since the Mind, as has been shewed, can by no means make to itself, must necessarily be the product of Things operating on the Mind in a natural way, and producing therein those Perceptions which by the Wisdom and Will of our Maker they are ordained and adapted to. From when it follows, that simple Ideas are not fictions of our Fancies, but the natural and regular production of Things without us, really operating upon us; and so carry with them all the conformity which is intended; or which our state requires’.

So, according to Locke (somewhat courageously interpreted), if your idea of a page just in front of you is in fact caused in you by the sort of thing that usually causes ideas of this sort (a page being just in front of you) then it’s putting you in touch with reality and – and here we get to the solution to our problem – because words such as ‘page’ just stand for the regular causes of the ideas associated with them, whatever those regular causes might be, it’s actually simply impossible for your idea of a page to have been caused in you by anything other than a page. If, per impossibile, it had been caused by something else, it wouldn’t be an idea of a page, it’d be an idea of that something else.

It’s natural to think that some sort of sleight of hand has gone on here. Haven’t we just shifted our problem from ‘How do you know that your ideas resemble the things that cause them?’ to ‘How do you know that your ideas are the ideas that you take them to be?’ Here’s a good question: if we had, would we have managed to turn it not just into a question that makes sense, but also into a question that we can answer? Unfortunately, this good question must await another time.

I recall an occasion when, as an undergraduate, in exasperation at the end of a tutorial I blurted out something like, ‘We still haven’t got an answer to the question!’ My tutor paused for a moment and then replied calmly, ‘No … But our question’s got a lot better.’ I imagine that you feel now as I did then. The easy way to dissipate that feeling would be by inattention to the problems which gave rise to it, but if you want a genuine cure, you’ll have to do something a bit harder: more Philosophy.

T. J. Mawson
12th August 2003

Suggestions for further reading:

G. Berkeley, A Treatise Concerning the Principles of Human Knowledge (first published 1710, but reprinted numerous times since), is the central text. A recent edition is edited by Roger Woolhouse as Principles of Human Knowledge/Three Dialogues (Penguin, 1988). The first seven sections contain Berkeley’s main arguments. D. Berman’s Berkeley, Experimental Philosophy (Phoenix, 1997) is a good (and short – less than sixty pages) introduction to Berkeley. His George Berkeley, Idealism and the Man (OUP, 1996) is more substantial as is A. C. Grayling’s Berkeley: The Central Arguments (Open Court, 1986). Either of these would be a reliable guide if you wished to explore Berkeley territory further. If you wanted to read a contemporary follower of Berkeley making his case, you couldn’t do better than look at John Foster’s The Case for Idealism (Routledge & Kegan Paul, 1982).