 Last video, last chapter, we saw that Russell is trying to answer that first problem of philosophy, whether we can know that objects are real. He gives an answer, he says yes, but you know the argument, well Lisa is still with a lot of questions, and you know the first question we really want to ask, which is the topic of this chapter, is well so okay so suppose we know that objects exist, now we got to ask ourselves what is their nature, and that question is really hard to answer. In fact the conclusion that he gives us here might be a little surprising, so this this one we're asking, he's asking what is the nature of matter, or what is the nature of physical objects, and he doesn't actually quite answer that question. Instead what he answers is what can we know about physical objects, and the answer basically, at least as he concludes here, and the next one is well we can know how they affect us. It's really nice out here, I think I've said in class, if I haven't said it I probably will, if you don't take a chance to go out and walk out, walk in our parks, and you know you're really missing out, it's good to be out here, I mean the colors are fantastic, the sounds of nature, the whole impact that all of, that all that I'm getting from my senses, the smell, the air is pretty fresh, it's hot of course, you know in San Antonio, but we know what are you going to do. Even the sun on my skin for at least for a little while feels pretty good. So yeah getting a lot of information from my senses here, and as we discussed there's just there's no doubt that I'm actually having that sensory data, there's just there's not a whole lot of doubt about it, or any doubt about that, and that's good right, I mean that's at least a piece of knowledge that I have. A question is whether or not that sense data tells us anything about those objects. Well one of the things that Russell again takes pains to point out is, you know the information that we get from the sense data is not from the object, I mean the the sense data, if the objects were just like what we get from the senses, then there wouldn't be any change in that sense data, right. We would know the object as it is without any kind of changes that we get from our sensory information. So you know just, you know we're talking about color, right. So right now the trees behind me they're pretty vibrant green, and you know that's all well and good, and that really isn't a problem. If I walk closer to the trees they're still pretty much the same color green. Well I don't know if you know where I am, I'm at a park called Comanche Lookout Park, and that tower behind me was erected a long time ago as a means of looking out to the other area around, you can see from miles around. So you know these trees look green from this distance, but if you take a look at trees that are much further away, say you know miles away as we're getting with this shot, I mean heck you can see a difference here, I've got you've got some trees that are a little bit less vibrant green than the ones that you saw earlier, and then the trees behind that which is even which are even further away, they're much more tinged with blue. Now the reason is is because there's lots of particulates in the air between myself and those trees, so that's affecting the color. But you know distance need not affect the color, I mean distance is one thing, but there's all sorts of things that do affect the color. I can change lights, I can have a variety of different lights on the color on the plant and that would change how it looks. I mean these trees look different in sunlight than they do in moonlight. So color is affected by proximity amongst other things, is affected by the conditions around it. So if color is affected by all these conditions, then what I'm getting from the since data is not just the object, there are other things involved, and if that's including me by the way, including me, I need to be here in order for the color to be here. So if all this is involved then the since data is not the object, I mean there's something else that's there. The same thing is going to be true with any of our sensory information, the smell of the trees, it's going to be different depending on whether I'm standing right next to it or further away. The touch, the touch of the tree can be affected whether you have hands, my hands are relatively soft. When you have somebody who works with their hands all day, their hands are going to be much more rough. What they feel on the surface of the tree is going to be different than what I feel on the surface of the tree. So the sensory information changes depending on conditions and not depending upon the object. So the sensory information is not what the object gives us. So sensory information isn't going to tell us much, so we aren't going to get much about these objects in terms of sensory information. They're not that color, they're not that smell, they're not that taste. Well what about space? What about space? I mean that's pretty fixed, right? Our knowledge, our spatial knowledge is pretty fixed. Well, I don't think about this picture again. We've got this picture at a distance of the trees in the background and you have the land there and everything. So just looking at this, how far away would you say the camera is from the point? It's really hard to tell just by looking at it. Our perception of space needs to be trained, really, to be able to tell distance. You've got to know what you're doing and that takes a lot of trial and error. It takes a lot of trial and error. So what we get from our senses isn't just going to do it right off the back. Or even the tower right there, right now looks pretty rectangular. And that's a spatial kind of judgment. But consider this angle. From this angle the tower is much more trapezoidal. It's narrower at the top than it is at the bottom. Now we've been trained to realize, well, that's just a trick of perspective. I mean, that's what happens to the shape of the tower. But you remember, it took a long time to figure that out. There's plenty of painting. There's plenty of artwork that didn't include perspective. And, you know, trying to figure out what people are saying about the spatial distance between the things could be a real problem. So space is even affected by our senses, right? What we get from a sense that it was space does not tell us exactly what's going on with space. Well, what about time? Well, now there I didn't say anything for a handful of seconds. Now without going back and rewinding and looking at the little clock, how many seconds was it? Now without going back and rewinding and looking at the little clock, how many seconds was it? I bet it seemed longer than it was. You know, our emotional reaction to time can affect our perception of time. You know, 20 seconds on the roller coaster is goes by a lot more quickly than 20 seconds, you know, holding a hot potato. Our perception of time is radically influenced by emotion by our sense data. Even, you know, time itself, right? Time itself, apparently, if you listen to what the science is telling us, is affected by gravity and speed. You know, it's affected by gravity and speed, but you wouldn't be able to tell the difference because your senses are affected by time, or at least affected by, you know, the causal conditions around you. So, what all this tells us, what Russell's pointing out here, is that our sensory information about the world around us, about these physical objects, is not just what the objects are. I mean, we're involved in that, too. And, you know, the real question is whether there's anything from the objects involved. We'll deal with that, he deals with that more in the next chapter when we're dealing with idealism. Now the question really, we have to ask ourselves, well look, if our senses don't tell us about the objects, if they're affected by all these conditions, you know, if space, even space and time are affected by our senses, our perceptions of space and time are affected by our senses and our emotional reactions and everything else, what do we know at all about these objects? I really can't see a ways around here. It's appropriately named to look out point, or command you to look out point. All right, well, so a sense data doesn't tell us a whole lot about these objects, since data is not of the object. Well, what about, I don't know, well, Russell says, well, what about the sciences, right? Sciences study physical objects a lot. Don't we know what physical objects are because of the sciences? Well, you know, a lot of what the sciences do, and this is not bad, right? This is good stuff. A lot of what the sciences do is, is a correlate phenomena to sense data, all right? So, you know, we talked about the green turning blue at the distance. And we know this because the particular, through the physical sciences, we know that in the distance is more blue than the green up front, even though it's all that is trees. We know that because it's particular to the air that affects the color, right? So, hey, we know that phenomena. You know, the sciences are going to tell us that all this light that I see around me, all these colors that I see because of the light, well, these are certain wavelengths of electromagnetic radiation. All right, well, so color is the light. Color is that wavelength of electromagnetic radiation. Well, Russell says, well, look, okay, hold on to the, hold on to the statement a second. Say, color is that wavelength, is that wave motion, is what he says, that wave motion of electromagnetic radiation. Well, is that the same thing as color? Because, you know, you can see, I mean, there's all kinds of motion out, the waves of motion out there that we don't think of color, right? So, this is the example that he brings up when he talks about somebody who was born blind, right? Somebody who's born blind can understand waves, right? You could take them on a ship and they can, they could feel the waves on the ship. They can feel the waves on the ship and they can understand waves in that way, but that doesn't translate into color. Nobody sails on high seas and says, wow, this is a really vivid red today. Nobody is on a, is on a calm flat sea and says, oh, the color of the waves is blue. The color of the water might be blue or sort of, you know, reflecting when, you know, having certain reflections or whatnot, but the color of the waves is not blue, right? That would be, or, you know, the wave motion is blue. That would be a strange thing to say. You know, think about it this way. Now, here's a color. So, this is a color, but nobody thinks of this as a sound. You're hearing sounds right now, but nobody sees the color as sound. But sound is what happens when wavelengths of concussions of air molecules hit our ears. Sound is registered, is, is measured in terms of waves, too. So, yeah, if, if light just is waves, this wave motion, then we would see wave motion and hear wave motion everywhere, right? No room with sound in it would be completely black. We would see light everywhere, but, you know, we just had to clap our hands and we would see light coming from our hands because that's a wave motion. No, that doesn't happen. Same thing is true, you know, same thing is, is true if we were in a brightly lit room with no sound, we would hear sounds all the time because we'd hear colors from the walls. So, to identify that wave motion with the phenomena, with the sense data, is a mistake. So, this, you know, this is Russell's point. It's like, look, the physical sciences are really good. He's, he's a fan of physical sciences, so am I, right? Physical sciences are really good for telling us what our relationship is to these objects, specifically the causal relationships. So, to put it in another way, I am experiencing color. You're experiencing color too from me, from what's happening out the distance, you from what's happening with your computer screen, right? I'm experiencing color and that's caused by a wavelength of electromagnetic radiation. Yeah, okay, and not just that, whatever's going on with my eyes and my optic nerve and what's happening here in the back of my skull. All of that, that object, the electromagnetic radiation that's hitting my eyes, all of that is causing the color. The, the sound, right? For, for me, you know, for, for the two of us, the sound is not caused by the same thing. For you, the sound is caused by a speaker and the electromagnetic radiation, a speaker with the wavelengths of concussions of air molecules in your ear. For me, the sound is caused by, you know, a variety of things. The bird, the vocal cords from the bird, the wind rustling through the leaves, the cars off in the distance, all these things that I hear, right? So, what the physical scientists tell us is our relationship to the physical objects and that's good, right? That's a good thing to know, that's not a bad thing and Russell's a fan and it's all mine. But that doesn't tell us about the nature of the physical objects. That doesn't tell us what they are, right? That only tells us its effects, namely the effects it has on our sense data. It's not that that's bad, right? It's not that it's bad that we, uh, that we know the, our causal relationships, our relations to these physical objects are also relations in terms of space and time. We know that too, sort of, and with these physical objects to a certain degree of error. But that doesn't tell us the nature of the physical objects and there's a difference between those two things. So what do we have left? What do we know about the objects around us? Well, hmm. So, uh, here's what Russell has so far. I mean this is from, uh, chapters one and two that we, uh, we have sense data, right? We have this private sense data and, you know, from chapter two we have that, uh, that we know sort of, uh, we know that there is an external world around us, right? The simpler belief has a better explanation. So that there's a world around us. Okay. Well, um, what else do we get? Well, here's the supposition. If our sense data doesn't tell us what the world is, right, if it doesn't tell us what its nature is, then we at least we know our sense data. At least we know we have our sense data. All right, so we got that, right? And, you know, if we have our sense data and we have the claim that, you know, you know, we were talking earlier, we had this claim that there's this world around us, we have our sense data, then at least we know, uh, how the world affects us, right? So I don't know the nature of the trees around me, but I know that between that and the sun and the atmosphere, uh, that they appear green, right? So here's what, here's what we have. Here's what we get from all this. You know, my senses don't tell us exactly what the world is like, but I know that I have my senses, I know I have that, I know that I, that there's a world around me, you know, we got that for chapter two, and I know how the world affects my senses. I know the relations between the world and my senses. So this doesn't exactly get us a nature of these objects, but it does tell us how these objects affect us, and that's something, that's something.