Lecture 7.1 Berkeley I

TOPIC: Lecture 7.1 Berkeley I Introduction to the Representational view of the mind. Berkeley s Argument from Illusion. KEY TERMS/ GOALS: Idealism. Naive realism. Representations. Berkeley s Argument from Illusion. READING: Berkeley, George. Excerpt from Three Dialogues Between Hylas and Philonous. (on E-Reserves). Focus on Dialogue p. 75-86 for this lecture, and the rest of the Dialogue for the next lecture. CONTENT: George Berkeley (1685-1753) was a British Empiricist, and he argues for a specific (and quite radical) position of Empiricism, namely Idealism. Idealism is the view that we can only claim to know OUR IDEAS about things, rather than things themselves. Accordingly, reality consists solely of minds and their ideas (Stanford Encyclopedia). His dialogues are fun and filled with dozens of arguments to support Idealism. Philonous is Berkeley s mouthpiece, and Hylas is the opposing character. I will outline one argument today, his Argument from Illusion. To understand his argument, I will first introduce an important debate about whether our perceptions track reality directly, or whether they track representations of reality. REPRESENTATIONALISM. The debate about perceptions involves a distinction between the external world, and the internal thoughts in our mind. On the one side, Naïve Realists argue that we perceive the world directly. For example, as depicted by the picture below, when we see a candle, we perceive the candle directly: Naïve (or direct) realism http://en.wikipedia.org/wiki/na%c3%afve_realism During the Enlightenment period, however, philosophers began to take seriously some worries that had been floating around since Plato s time. One worry is that if we perceived the world directly, then it would be

impossible to mis-interpret the world. Yet, we do mis-interpret the world when we experience visual illusions such as shown below: But what about illusions? Illusion creates a problem for naïve realists as it suggests our senses are fallable, perceiving things that aren't there. In this illusion, the lines are horizontal, despite how they appear. As an alternative theory, Representationalists argue that we REPRESENT the world in our minds. On this view, we store representations (in some kind of mental states) in our minds, and when we think about the world we recall these representations. For example, when we look at a trail of water with reflecting light, what we represent is a cloud or a rainbow. What our minds create is sometimes different than what is really there. For example, when we look at the picture below, our minds conjure up the IDEA of two triangles: Does your mind represent two triangles? There is a difference Between what we perceive (how we represent the world in our minds) and how the world really is Representationalists can answer why illusions occur by explaining that we perceive (mis-) representations of the world, rather than what is in the world directly. If we saw the world directly, then we would perceive the following circles as the same size. But we don t-- our minds create a representation of one circle as larger than the other:

Your mind represents the second orange circle as larger than the first. And, of course, the famous Ames room takes advantage of the fact that our representations are different than the world: http://images.encarta.msn.com/xrefmedia. AMES ROOM If we were representing the world directly, then why do we see the child as so much larger than the woman? There is one more popular illusion which is important to know about (you ll probably watch this video in a psychology class.) Go to http://viscog.beckman.illinois.edu/flashmovie/15.php, watch the video, and record how many times the black team (the team with black shirts) passes the ball. I won t give away the illusion, but you can read about it at http://en.wikipedia.org/wiki/inattentional_blindness. Also, the creators of the test, Chabris and Simons, have a new book out about perceptual (in)abilities: http://crownpublishing.com/2010/05/18/pressrelease-the-invisible-gorilla-by-christopher-chabris-and-daniel-simons/ Using the case of illusions, representationalists may convince us that there is a REPRESENTATIONAL MEDIUM between us and the world. Things in the world pass through our eyes and visual system and most likely other cognitive mechanisms to create representations (ideas, or what we are conscious of) of those things. And, if our mind does that with illusions, then there s no reason to think that our minds don t represent the world all the time. In Berkeley s Dialogues, Philonous and Hylas are representationalists, but they disagree about what the representations are. Hylas thinks that our mind s representations are about the world itself (independent of whether anyone was perceiving the world), and Philonous thinks that all we have access to is the representations we receive, not about a mind-independent world. BERKELEY S ARGUMENT FROM ILLUSION. Philonous (Greek for lover of mind ; Berkeley s mouthpiece) is having a conversation with Hylas (Greek word for matter ; a scientific realist). Philonous makes a bold statement: [T]here is no such thing as what

Philosophers [scientists] call material substance, I am seriously persuaded. (75). It seems as though Philonous will argue that there are no material things. This is a statement that goes against all our common sense beliefs, because we think that of course things exist: There are tables and chairs and trees. The conclusion that material things don t exist is one interpretation for what Philonous will argue, but the received view is that Philonous conclusion is a little weaker. He will argue that we are not warranted or justified in believing that there are material things. Hylas first offers a fairly common-sense notion: To exist is one thing, to be perceived is another (76) where existence means: a real absolute being, distinct from and without any relation to, their being perceived (76). Hylas separates MATTER or material substances, from PERCEPTION of matter. For example, a table is a material thing that will exist, independent of anyone having a representation or perception of that table. This is a view shared by any scientific realist who thinks that there is a real existence which we can discover. If we think that planets or rocks can exist even if there were no humans around to perceive those things, then we are scientific realists. Thinking that there are things that can exist independent of perceptions means that we think there is a reality that is mind-independent. This is Hylas position. Philonous, however, points out that what we KNOW of things only comes from our perceptions of those things. The first thing to be clear about in Berkeley s dialogue is that he will focus on SENSE-DATA, which is any information (pictures, words, sights, sounds, smells) that is received through your five senses. Sense data includes colors, pain, smells, sounds, odor, etc. and is gained by eyes, ears, nose, mouth, and by touch. Philonous asks Hylas what he knows about HEAT. Hylas names some properties that heat feels a certain way, and is painful if it is too hot. Philonous then argues that heat and other sense data cannot exist without the mind in any unperceiving substance. 78. For example, the heat in the stove cannot be IN THE STOVE, because (as Philonous argues) HEAT is FELT, and a stove cannot feel. As another example, the pain of a pinprick does not exist in the pin, rather the pain exists in our fingers. As another example, during a lunar eclipse the illusion of a large orange moon on the horizon is sense-data in our minds, not a fact about the moon (the moon doesn t all of a sudden become larger when it is on the horizon). So, what we know from the stove, pin, and the moon, are only the sense-data we receive in our minds. Now, you will probably respond like Hylas does, by distinguishing between two kinds of substances PRIMARY QUALITIES (extension, solidity, motion, substance) that define what the object is, and SECONDARY QUALITIES (color, tastes, texture, smell) that can vary without changing the essence of the object. (Incidently, the distinction between primary and secondary qualities is attributed to John Locke). For example, you may argue that the solidity of the table will exist even though the color changes with the changing light. But Philonous argues that Secondary and Primary qualities cannot be separated. If Philonous shows that Secondary qualities have no existence, then Primary qualities have no existence (independent from our experience of them) as well. He does this by explaining that what we know about the primary qualities comes from the senses as well. We do not know about how solid the table was unless we saw and felt the table. So, all we know is the sense-data that we receive. For Berkeley all we are aware of is our ideas or representations of the world. I will focus on one argument that Philonous gives, called the Argument from Illusion (p. 78). Philonous says Suppose now one of your hands hot, and the other cold, and that they are both at once put into the same vessel of water, in an intermediate state; will the water not seem cold to one hand, and warm to the other? You ve all experienced this: If your hands are cold from the snow outside, and you run them under cold water, the water will feel warm. If one hand is hot and another is cold, then the water will feel like two different temperatures. When Hylas agrees that the water seems to be cold and hot at the same time, Philonous objects that objects cannot contain contradictory properties. This is simply the law of non-contradiction. Something cannot both

exist and not exist, or be red and not red at the same time. Likewise, the water cannot be both cold and hot at the same time (by law of non-contradiction). Hylas concedes: heat and cold are only sensations existing in our minds. 78 Berkeley s ARGUMENT FROM ILLUSION is: P1. Sense-data change and vary across different people, time, and context. Senses give contradictory data. P2. An object can t have contradictory properties. (something can t be warm and cold at the same time) C. So the sense-data cannot be part of the object itself. The first premise explains that sense-data is relative to people (sour candy might taste good to you but utterly bitter and repulsive to me), time (the red in the clouds vanishes a moment later), and context (you will see that the table is a certain shape if you stand across from it, and I will see that it is a different shape by standing in a different position). Now, if we were to say that the properties of repulsive and good belong to the candy, then we d have a contradiction. Something cannot both be repulsive and good at the same time. Does the red really exist in the cloud one second, and then disappear? No, something can t both exist and not exist. And, the table cannot be one shape and an entirely different shape as well. So, the tastes, colors, and shapes, cannot be part of the objects themselves. As another example, consider that orange juice tastes sweet before you brush your teeth, and bitter after you brush your teeth. But can the orange juice be both sweet and bitter? It is more likely that the sense-data we receive (sweet and bitter) say more about what our minds are perceiving, than it does about the orange juice itself. Think of other examples and share them on the discussion board. The conclusion to the Argument from Illusion is that the sense-data is not part of the object itself. Colors or tastes or textures are not part of objects, rather, they are sense-data that exist in our minds. His reasons are that the sense-data we get from objects are relative and contradictory. It is as if what we are receiving from objects is a kind of illusion since the sense-data doesn t tell us true properties of the objects themselves. Since objects can t contain contradictory properties, then those properties are not part of the objects. You may see a similarity to Descartes Wax argument. Descartes argued that what our senses tell us about the wax is a bunch of different and contradictory properties. But whereas Descartes then chose to place his trust on what his pure reason tells him, Berkeley does not take this route. Descartes chose not to trust the senses, but you will see that Berkeley places full trust in the senses. For Berkeley, ALL WE KNOW is what our sense-data tells us. Berkeley is an extreme empiricist. Indeed, Berkeley believes that all we are warranted in claiming is that our IDEAS give us information. Our sense-data/ ideas exist, but we cannot be justified in saying that anything mindindependent exists. The point of examples like this was to show that the secondary quality of heat is not a real property of the object, it is a product of the way you represent the object. The same water cannot be both warm and cold, but this is just what our senses tell us in this example. So using his relativity arguments Berkeley has attempted to show that secondary qualities are not properties of the object. How does he argue against the primary qualities? With more relativity arguments. Philonous goes on apply similar argument to heat (78), taste (79), sound (79), colors (80-82), and then primary qualities: motion (83), solidity (84), extension (85), substance (85-86). Explain one or more of these arguments on the discussion board. These arguments are important, because Berkeley is careful to

consider possible objections. For example, you may object that we KNOW that atoms exist because we can see them in a microscope. But Berkeley has a reply: Tools such as microscopes or telescopes only give us MORE SENSE DATA. They do not tell us about the real object, they only SHOW us more images. See page 81 for his discussion of microscopes. For example, you may object that we can use a thermometer to tell us the REAL temperature, even if two people feel hot or cold. But what the thermometer does is give us sense-data from our eyes (we read the numbers), and then we translate what the numbers mean (i.e. 71 degrees Fahrenheit). Do those numbers somehow tell us a REAL property of the air? Philonous would say that it only gives us more sense-data. We saw the numbers, and so now we have sense-data of the numbers we read from the thermometer. So, it won t do to say that thermometers detect the real heat, because thermometers, or microscopes, or EMF readings only give us OTHER SENSE DATA. But why should I privilege the thermometer reading of 71 degrees, over my hands that tell me the water is cold or warm? Now, instead of having sense data of warm and cold from our hand, now have other sense-data, a reading from a thermometer that says 71 degrees. Or we can see a reading of another instrument that detects what we call motion and kinetic energy. Whatever instrument of measurement that you give me, you re only adding further sense data. It just compounds the problem. As we will see next time, Berkeley will argue that we ONLY have access to the sense-data in our minds, rather than objects itself, and so we cannot say anything about the objects other than what our sense-data tells us. A HELPFUL ANALOGY: THE INVERTED SPECTRUM THOUGHT EXPERIMENT: Inverted spectrum thought experiment 12 The inverted spectrum thought experiment (which was originally Locke s thought experiment, but I will give you the modern version) has you imagine the possibility that someone s brain/ eyes could be wired in such a way that they were seeing a different color than someone else. Imagine that Smith was an invert and he saw green when he looked at a strawberry. Jones sees red. Also imagine that Smith and Jones were both taught to call the color of the strawberry red. How will Smith ever know he was an invert? How will Smith or Jones ever be able to tell the real color of the strawberry? Why privilege one theory over the other. One theory says that the real color is (green) the other says that the real color is (red). Isn t it more parsimonious to say that the real color does not exist, only people s senseperceptions of the color that they are seeing exist? Think about how Berkeley might use the inverted spectrum thought experiment as supporting evidence for his arguments for illusion. Berkeley says people s sense experiences are relative to the particular senses that people receive. He says 1) many people have different sense experiences, i.e. what you see of the table is a particular

shape and color (from light reflections) and what I see standing over here is a different shape and color. 2) The same person has different sense experiences of a single thing. I.e. When I see a cloud or rainbow I see colors, but the colors change or fade when I walk closer. 3) we can do the same thing with time. At time 1 the sunset gives bright red colors in the sky, and at time 2 the colors go away. Where did the colors go, if they are part of the sky itself? Isn t it more parsimonious (a better explanation) to say that the colors aren t entities that exist in the sky, but rather part of our color-detection mechanisms, e.g. our eyes? Berkeley says that if heat, for example, is a property of the water itself, then how can we know the real heat, if what we receive is a cold sensation from one hand and a warm sensation from the other hand. It s contradictory to say that the water is both cold and hot. It won t do to say that we have inter-subjective agreement (namely, other people agree with you about what is being seen). Just because we all apparently see the same color, that just means that we can all apparently have access to the same sense-data. Inter-subjective agreement does not say that we all have access to the real world, or the real colors, only that we agree on the same sense-data. We could all be wrong, or we could all have the wrong sorts of sense-mechanisms which may not ever tell us the real properties of objects. WHO IS THE SKEPTIC? I want to flag that Hylas accuses Philonous of being a skeptic (p. 75). Recall that Epistemic sckepticism is the view that we are not justified in making claims to knowledge (or that we do not know things). On the face of it, Philonous sure looks like a skeptic. But as you read the dialogue, ask yourself, Who s the true skeptic? Philonous (Berkeley), or Hylas (a scientific realist). The way I see it, by the end of the dialogues, it seems (to me at least) that Hylas is the real skeptic in this debate. The skeptical argument in Berkeley is subtle. Here's what I figured out in connection to scientific realism which is a doctrine about how there is a true nature to reality which is mind-independent. Scientific realists say that the aim of science is to discover true laws of nature, and to discover the nature objects in space or under microscopes which we may not conceive of yet. For example, we say that there are galaxies in the sky which we have a little bit of empirical evidence for, and then we conclude that there must be thousands of galaxies that we haven't seen yet that also exist. Scientists claim that some day we'll find out. But Philonous' (Berkeley's) point in calling Hylas (the scientific realist) a skeptic is that the scientific realist 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 the only way we could ever know those things. ASSESSMENT: Be able to summarize Berkeley s Argument from Illusion. Try your summary on the Discussion Board. DISCUSSION QUESTIONS: Do you agree with Berkeley that we cannot know what properties objects have because we each have different experiences/ sense-data of those objects? Critique Berkeley s Argument from Illusion. The argument is a form of general Arguments from Relativity, which says that because people have different relative experiences of X, then we are not justified in saying X exists. We

saw a similar argument from Pojman. Can we conclude that X does not exist because people have different experiences of X? Do you think that other people (or you) might have an Inverted Spectrum visual system, where you see or experience something radically different than other people? How might we argue that all our sense-data is the same? Do you think there is a mind-independent reality? How would you argue that our sense-data tells us something about the real nature of objects? Just as a poll, how many of you have heard of the Gorilla Video that tests our visual perception/ attention? Do you think it provides good evidence that what we perceive are representations of what we are attending to, rather than reality itself?