1 TOPIC: Lecture 7.2 Berkeley Lecture Berkeley will discuss why we only have access to our sense-data, rather than the real world. He will then explain why we can trust our senses. He gives an argument for the existence of God. He ends with a small discussion about skepticism. KEY TERMS/ GOALS: Esse est percipi Berkeley s No Independent Access argument. Berkeley s Master Argument Solipsism Berkeley s Argument for the Existence of God. READING: Berkeley, Three dialogues between Hylas and Philonous focus on p. 86 (chapter 9) to the end (p. 93). CONTENT: In the first chapters of Berkeley s essay, Philonous (Berkeley s mouthpiece) argues that we are not justified in thinking that we have knowledge about properties of things themselves. We do not know that there is heat (78), taste (79), sound (79), colors (80-82), motion (83), solidity (84), extension (85), substance (85-86) in the world. Rather, all we can claim to know is that we have representations or sense-data of these things. He argues that we don t know that the stove contains heat, we only know what our senses tell us: that heat feels a certain way (we are in more or less pain), or that colors look a certain way. Recall that he uses his Argument from Illusion to conclude that we cannot claim that colors, heat, etc. belong to the objects themselves, since colors, heat, etc. vary. Since those properties vary, we would either have to say that the objects have varied and contradictory properties (which is not an option because objects can t have contradictory properties), or we must say that those properties belong to our mind/ ideas rather than the objects themselves. For example, if our two hands are hot and cold, and we stick them in water, then the water feels both hot and cold. But the water cannot be both hot and cold, so we must conclude that the hot and cold properties are not part of the water. Those sensations tell us more about how our mind is interpreting those sensations, and sensations are part of us, not the water. If we agree with Berkeley that our sense-data does not tell us about real objects themselves, then it is a small step to conclude that we know nothing about the real world. The real world is what Hylas, the scientific realist, believes in. Hylas thinks that there are tables and chairs, not just our sense-data about what tables and chairs look or feel like to us. The real world is supposedly independent of our knowing or perceiving it. Rocks and water would exist in the real world even if there was no one around to gain sense-data of them. In the following two arguments, however, Philonous will argue that we are not warranted claiming that we know anything about this real world.
2 THE MASTER ARGUMENT : Esse est percipi. In chapter 9, Philonous reminds Hylas that the properties that we think belong to objects themselves can only exist if minds can perceive those qualities. The color red, for example, is not red without some creature there to see it. Pain does not exist in the world, but in the finger and the mind that senses the pain. (Hopefully, you will have some objections that you will raise in the discussion board.) Philonous offers Hylas a challenge of offering a proof or argument that qualities, or any sensible object whatever can exist without the mind. Hylas takes this challenge, which will remind you of the often-raised question, If a tree falls in the woods and there is no one to hear it, then does the tree make a sound? He says that he can imagine that it is possible for a tree or a house to exist even if there were no creatures to perceive it. This tree or house is in a solitary place, and even if no one ever saw it, Hylas thinks it still can exist. Again, he is trying to show that there can be a mindindependent reality. Philonous then points out that instead of showing that the tree exists in reality, all Hylas has done is shown that Hylas himself can think of it. Philonous says The tree or house therefore which you think of, is conceived by you... And what is conceived is surely in the mind (86.) In other words, Hylas has simply given another example of sense-data his thoughts or ideas about a house or tree. But sense-data, we already agreed, is part of the mind, not part of the world. Hylas concedes, As I was thinking of a tree in a solitary place, where no one was present to see it, methought that was to conceive a tree as existing unperceived or unthought of, not considering that I myself conceived it all the while. But now I plainly see, that all I can do is to frame ideas in my own mine.... And this is far from proving that I can conceive them existing out of the minds of all spirits (86). Hylas has failed the challenge, since he only provided an idea of the tree or house, not of a mind-independent tree or house. Philonous comments that all Hylas has done is conjured up an idea of a tree, and then call that idea a real tree. He says: But say you, surely there is nothing easier than to imagine trees, for instance, in a park, or books existing in a closet, and no body by to perceive them. I answer, you may so, there is no difficulty in it: but what is all this, I beseech you, more than framing in your mind certain ideas which you call books and trees, and at the same time omitting to frame the idea of any one that may perceive them? 88 Our evidence for saying that something is real is by pointing to our sense-data (what we see, feel, smell). But our sense-data is not the thing itself (as Hylas would want to say). Our sense-data is only ideas in the mind. Saying there is a tree is shorthand for saying I perceive a tree. Our perceptions, representations, or sense-data is the only evidence that we can provide about the real world outside our minds. But that evidence is still in the mind. The evidence or justification for saying there are mind-independent objects is lacking. We are, therefore, not justified in saying that we know that those objects exist.
3 Again, Pholonous says, Lecture 7.2 Berkeley Lecture When we do our utmost to conceive the existence of external bodies, we are all the while only contemplating our own ideas. But the mind taking no notice of itself, is deluded to think it can and doth conceive bodies existing unthought of or without the mind; though at the same time they are apprehended by or exist in it self. The Master argument is traditionally outlined as follows, P1. If objects exist mind-independent, then they could exist without anyone thinking of them. P2. Whatever is conceived (an idea in the mind; a thought; perceived) exists in the mind. P3. It is impossible (and a contradiction) to conceive of something which is unconceived. (I can t think of something that can t be thought of: I cannot see an unseen tree; I cannot have an idea of a tree in my mind that exists in no mind). C. Therefore, there cannot be objects that exist independent of minds. (88: no idea can exist without the mind ). If you doubt the conclusion, then try it out: Provide an example of something that exists without you sensing or thinking of it. The kind of example might be something that cannot be seen, heard, felt, tasted, or thought of. Remember to critique each argument that we discuss, using the six ways to critique an argument, and share your critiques on the discussion board. NO INDEPENDENT ACCESS ARGUMENT Berkeley argues that all we can be aware of (all that we can conceive or have an idea of) is our sense-data. Here s a little scenario to explain what that means: Imagine that a person, Smith, has a box on his head with a screen inside. The screen receives images from a camera hooked onto the outside of the box. Smith can see the camera screen, but nothing else. In other words, all that Smith has access to is what the images on the screen show him. He can see images of tables and the room outside the box, but he cannot see the tables and room directly. Now consider that SENSE-DATA, for Berkeley, is analogous to receiving images on the screen. Sense-data includes any information that we get from our five senses: images of tables, the feel of the texture of the table, the smell and taste of the table, etc. Berkeley will argue that we ONLY have access to sense-data, or images that are filtered through our senses. Here is the outline for his No independent access argument: 1. We have access to the contents of our own mind. E.g. we receive sense-data. We can t deny being conscious of sense-data. If we can perceive something (x), then we perceive sense-data. 2. Our mind gives us sense-data of Secondary qualities (colors that we see, smells). 3. Secondary qualities are not distinct from Primary qualities.
4 4. Mind-independent objects cannot produce sense data. 5. Therefore, we cannot perceive mind-independent objects. We only have access to sense-data. This argument is a combination of his earlier arguments. The first premise is simply an empirical observation that humans can perceive or sense things. The second and third premises also state that we can perceive secondary qualities (colors, smells), as well as primary qualities (substance, extension). The fourth premise is taken from an argument that explains that things like stoves are incapable of feeling. Heat is what we feel, not something that the stove feels. Pain is something in our fingers/ mind, not in the pin itself. The conclusion is that we are kind of stuck in this prison of sensations, and we cannot get out of it, much like Smith cannot see outside the box that is stuck on his head. Berkeley s IDEALISM states that what is real is sense-data and our ideas. Remember Berkeley is an empiricist. This means that ALL our knowledge must be derived from the senses. But now, you might be wondering how we can trust our senses to tell us anything about the world around us. Recall how perception works for Berkeley. What we are aware of is not the object directly, but our representation or idea of the object. Berkeley argued for this with his relativity arguments. Instead of saying (like Descartes does) that our senses give us faulty information, Berkeley says that all we have to go by is our sense-data. He coins the term, Esse est percipi which is Latin for "To be is to be perceived. For Berkeley all we are aware of is our ideas or representations of the world. It is almost like Berkeley is giving a new conception to existence. Existence just is perception. Berkeley DOES say that there are trees, birds, clouds. But he means that we have sense-data of trees, birds, etc. Berkeley has a worry, called the Persistence of Objects, that drives him to give a stronger argument for why things exist. His worry is this: If existence is to be perceived, then why doesn't the room just disappear when we leave it? Can we say that the room remains the same each time we leave and re-enter it? That is, if we were to take Berkeley s arguments seriously, then we walk out of the room and no one is around to perceive the chairs, then we d have to say that those chairs disappear. But we don t want to say that the chairs disappear. We want to say that the chair is the same chair now as a moment ago when I was looking at it. He says,...sensible things cannot exist otherwise than in a mind or spirit. Whence I conclude, not that they have no existence, but that seeing they depend not on my thought, and have an existence distinct from being perceived by me, there must be some other mind wherein they exist. 89. Berkeley himself did not perceive the chair when he left the room, so SOME mind had to perceive/ conceive it. On his view, the chair has to be someone s idea of it some mind has to perceive or conceive of the chair for it to exist. It s not like the chair can conceive of itself the chair cannot sense things. But if matter cannot exist without being perceived (Master argument: esse est percipi), then some mind must be perceiving/ conceiving of it. How does Berkeley argue that objects persist even if no one is around to think about them? His argument is in the Second Dialogue p Read this dialogue and write an argument outline. ARGUMENT FOR THE EXISTENCE OF GOD. Since the room does not disappear when we leave it, then some mind has to be perceiving/ conceiving of the room. That mind, of course, is God s mind. Now, before you think that this way out of the problem is cheap, consider that Berkeley actually gives an argument for God s existence. The argument is on page 89-90:
5 it is evident that the things I perceive are my own ideas, and that no idea can exist unless it me in a mind. Nor is it less plain that these ideas or things by me perceived... Exist independently of my mind, since I know myself not to be their author... They must therefore exist in some other mind, whose will it is they should be exhibited to me 89 The conclusion is: There is a mind which affects me every moment with all the sensible impressions I perceive (90). This mind is wise, powerful, and good, beyond comprehension (90). Berkeley argues that there must be some being that is powerful enough to conceive of everything that we are capable of sensing. His reasons for saying that there must be some being, is that he himself did not conjure up all the things that he perceives. When he opens a room and is surprised to see a grand piano in it, he himself did not conceive of the grand piano. And, since the grand piano doesn t exist of its own accord, some other being must have been having an idea of the grand piano. Here is the argument outline for Berkeley s Argument for God s Existence: P1. I receive sense-data. P2. I am not the original author of the sense-data. I did not will certain sense-data to be received. P3. Something must be the original author/ cause of the sense data. (all things have causes) P4. God is the author/ cause. We may call that being God and God has to have the property of being powerful enough to share his ideas with everyone who perceives them. God is the author of Berkeley s sense-data. This means that God has the property of being able to cause sense-data in our minds. God is also, Berkeley thinks, a benevolent God. I think that this is a pretty clever solution to the problem of why objects persist even though we are not thinking of them. Incidentally, the argument has similarities to a cosmological argument. The empirical fact is that Berkeley has an idea (say, of a grand piano when he walks into a room). Then, since all things must be caused, Berkeley concludes that there must be something that caused that idea. Since it cannot be the piano itself, it must be a powerful mind that caused that idea. The argument is also similar to Descartes argument for the existence of God (recall that Descartes said that something infinite, all-good, all-knowing etc. must have caused his idea of an infinite being, and that something is God since it has the properties of infinity, all-good, allknowing, etc.) BERKELEY S ONTOLOGY. The last thing that must be discussed is how Berkeley brings back the world, so to speak. Berkeley s idealism maintains that nothing exists except ideas. His ontology, therefore is MIND and GOD. Mind/ ideas and God are the only things that exist. (Material things do not exist). In a way, Berkeley is giving a more parsimonious ontology than someone who thinks that a mind-independent reality exists. Parsimony is a feature of science that says that among two competing or alternative theories, choose the one that posits the least amount of ontologies/ entities. E.g. choose the theory where you need to explain the least number of kinds of things that exist. If someone says that mind, matter and God exist, then they need to explain three things (how material things came into existence, and the nature and existence of mind and
6 God). But Berkeley only needs to explain two things about the nature God and our minds. Berkeley has a parsimonious theory. Instead of having to explain mind, matter, and God, all his theory has to explain is mind and God. He cut s out matter. SOLIPSISM: I want to warn you against a common misinterpretation of Berkeley s idealism. The extreme position is called SOLIPSISM, which is the doctrine that nothing exists except onseself. Solipsists deny the existence of external world, other people, etc. There is a song called Only by Nine Inch Nails (Trent Reznor) that expresses this idea. The character in the song says There is no you, there is only me, and he goes on to explain how I made you up to hurt myself. But Berkeley is no Trent Reznor. Berkeley does not claim that only one mind exists there are lots and lots of minds and ideas. There is an idea for every sensory experience that anyone can have. So BERKELEY IS NOT A SOLIPSIST. By the end of the dialogues Berkeley says that we are justified in believing in trees, birds, etc. The only thing to keep in mind, however, is that he has a different interpretation of what matter is. Berkeley discusses how we can walk around in a park full of trees and lovely smells. He DOES believe that lots of sensible qualities of things exist: like trees as long as we know trees means as a bundle of perceptions that we receive. Birds and trees are actually ideas or sense-perceptions of birds and trees, and we are certainly warranted in knowing that sense-data exists. In my opinion I think that Berkeley is asking what more we need other than ideas and perceptions? Why do we need to posit things about the objects true nature of the real world? Isn t it good enough to have available to us all the sense perceptions that we do have in this beautiful world with lots of sense-data around us? BERKELEY S SKEPTICISM (?). Let me return to a question I asked last time, about who is the true skeptic, Philonous or Hylas? Remember that we may have started out thinking that Philonous was the skeptic (someone who things that we cannot claim to know that things exist), because he argued that we are not justified in claiming that there is a mind-independent world, or material things apart from our sense-data. However, consider what Hylas says: the reality of sensible things consists of an absolute existence out of the minds of spirits, or distinct from their being perceived. Hylas is thinking, like any good scientific realist, that there may be an ultimate nature to reality that we may never know about. For example, there might be other planets in other solar systems that exist, even though we may never know about them. Scientific realists say that the aim of science is to discover true laws of nature, and to discover objects in space with telescopes or objects under microscopes which we may not have discovered yet. But to claim that we do not know those things is part of the definition of a skeptic. But Philonous' point in calling Hylas a skeptic is that Hylas is the one positing the existence of things that we may or may not ever know. Scientific realists put the object of their enquiry too far removed from the senses, which is, for an empiricist, the only way we could ever know those things. Philonous, on the other hand, grants that there are (sense-data about) trees, woods, rivers. So, in your opinion, who s the true skeptic? Philonous (Berkeley), or Hylas (a scientific realist).
7 ATTEMPTS TO REFUTE SKEPTICISM. As a closing to our unit on Epistemology, I want to mention a couple attempts to answer the epistemic skepticism that we have considered. Recall that Descartes started out giving us arguments for why we should be skeptical about our sensory knowledge. Although we did not review Hume s skepticism of inductive reasoning, he is skeptical that we can make claims about causation. And Berkeley, of course, makes us consider whether we should say that we know anything at all about reality independent of our experience of it. Here is a famous story about a friend of Berkeley s, Dr. Johnson, who attempted to give a simple argument to prove Berkeley is wrong. Berkeley and Dr. Johnson were walking on campus one day and Dr. Johnson accuses Berkeley of being crazy to question the existence of things. Dr. Johnson stubs his toe on a rock and then says, I refute you thus. Dr. Johnson s argument is a form of reasoning called argumentum ad demonstratum, or argument by demonstration. He demonstrated that things (a rock) exists by kicking it. Why does this argument fail? The reason that this argument fails is because all Dr. Johnson has done is provide more sense-data. He saw a rock, and then felt the pain of the rock against his toe. But an image and feeling of pain does not prove that there are mind-independent things, it only shows that one can receive more sense-data from the world. In the 20 th century, G.E. Moore and a host of other philosophers called Ordinary Language Philosophers (Russell, Wittgenstein, Quine, Carnap, etc.) engaged in the skeptical arguments from Descartes, Hume, and Berkeley. Moore, for example, has an article called Proof of an external world. In it Moore gives another argument by demonstration. He holds up one hand and says, this is a hand. Then he holds up his other hand and says this is hand. Thus there are two hands. His argument is a proof that there are things in the world, namely hands, and you can multiply entities here to argue that anything you can show exists (tables, chairs, etc.). I leave it up to you to consider whether these arguments are good enough to prove that there is a mind-external reality. You must also attempt to come up with your own arguments, and share them on the discussion board. ASSESSMENT: Be able to summarize Berkeley s No Independent Access Argument, and his Argument for the existence of God. Give 1-2 paragraphs of each argument and explain the premises. Try your argument summaries on the Discussion Board (They will be on the final exam). DISCUSSION QUESTIONS: Are you an empiricist (All knowledge comes from the senses) or a rationalist (some knowledge comes from pure reason)? Are you convinced by Berkeley s arguments that we are not justified in claiming that we know about a mindindependent reality? Critique Berkeeley s arguments. How else can we explain the persistence of objects (objects exist even if there is no one to perceive them) other than by employing God as an explanation?