 So Russell has yet to fully dispel the specter of idealism in the previous chapter. Remember, he was talking about idealism. He's given us an argument that says he was simpler to believe that they're physical objects, that it's false and everything that exists is just mental. But he's yet to really kind of put the nail in the coffin on the view. Now his attempt at doing this is to say that Barclay's argument has a deep flaw in it, namely that he fails to account for these two kinds of knowledge. In this chapter, in this section, Russell kind of elaborates on the distinction between knowledge by acquaintance and knowledge by description. And he thinks that this is gonna allow him to, you know, finally dispel idealism from our philosophical problems. So that's what we're gonna do in this chapter. We're gonna take a look at what Russell has to say about the distinction between knowledge by description and knowledge by acquaintance and knowledge by description. So I don't know if you've been out here before, but this is the Japanese tea gardens, or yeah, the Japanese tea gardens. It's really vibrant out here. I mean, there's a lot of people out here which I'm sure you can hear. You can hear the waterfall off in the distance. The plants are green and lush. They must have done a lot of recent planting and it's water everywhere, thanks to the recent rains. There's a lot that I'm getting through my senses. Now, what I'm getting through my senses, that's what I'm directly acquainted with, right? That is at the forefront of my consciousness. The water, the plants, the humidity and the air, the sound from the waterfall, all these things are involved causally with what I'm getting through my senses. But I don't have direct access to those things. What I have direct access to are my senses and the content of my senses. So this is a typical example of what I get through knowledge by acquaintance. This is what I'm immediately aware of. There's no middleman between my senses and my awareness. There's a middleman between the waterfall and these kids and the plants and everything and my awareness. And that's my senses, my senses are the middleman. But what I'm directly aware of, that's the senses. So what I get from my senses, that's part of what I get from knowledge of things by acquaintance. There's more than I get by knowledge by acquaintance. It's really interesting, Russell says this. If knowledge by acquaintance was limited to just the senses, well, then we would know a whole lot. Other things that I'm aware of directly what I have through knowledge by acquaintance is memory, the contents of what I remember. So I'm gonna remember today, at least for a little while, hopefully. I remember teaching this morning. I remember friends and family, I remember events. Now that immediate awareness of that immediate awareness what I have at the forefront of my consciousness, that's the memory. That's what I have by knowledge by acquaintance. Something else I have by knowledge by acquaintance is introspection. So this might sound a little strange, but my awareness of my awareness. So right now I hear the waterfall. And by knowledge by acquaintance, what's at the forefront of my consciousness is the sound of the waterfall. But what's also there is my awareness that I'm aware of the sound. My awareness that I'm aware of the sound. Now, you might start saying, well, can I be aware of my awareness of the sound? Well, maybe. I should list an upper limit of what goes on there, but we're not gonna worry about the upper limit of awareness of awareness. For the moment, just as an example of something else that I have by knowledge by acquaintance is my awareness of hearing that sound. And finally, the last thing that we have by knowledge by acquaintance, where Russell gives us, is what he calls knowledge of abstract ideas or universes. So we've had some examples of universes in class. He gives some whiteness. I think Brotherhood was one that he gave an example of. Now these are concepts applied in many different things. Numbers are also universals. These are abstract pairs, trios, quadruples. Logical relations, these are universals. So we've talked about logical relations before, sufficient necessity, contrariety, subcontrariety. And then we get the rest of logic from those relations. Now, Russell says we have that through knowledge of acquaintance by acquaintance. The act of thinking of these universals he calls conceiving. And the universe of the self he calls the concept. That's a really interesting thing to say. Now, we're not gonna be able to address that till we get to the chapter on our knowledge universals. I think that's where he's gonna elaborate on that more. So we're definitely gonna put a bookmark on that one because that's a curious thing to say. We're somehow directly aware of universals. That's interesting. So, knowledge by acquaintance. Sensory information, memory, introspection. The awareness of my being aware of the waterfall and universals. And from this, Russell says, all of the knowledge is derived. From this, all of the knowledge is derived. So we'll see what he has to say about that in later sections. So that's something you don't see every day. Waterfall in Texas. Well, you are not here. You can't see the waterfall with your own eyes. What you see is an image on your computer screen or your phone or whatever. The waterfall at the Japanese Tea Guards in the Sanctuary of Texas. It's about 30 feet high. I'm sure there's a certain amount of water that falls from the waterfall. There's a certain amount of water that goes through here. The rock face has, looks like various kinds of stuff growing on it. So there's even a rate at which it falls. So the waterfall in the Japanese Tea Guards, Sanctuary of Texas, that's a definite description. There's one and only one thing that fits that description. There it is. Now, you're not here. You can't see it. Technically, in a way, I can't see it either. All I can see is the perceptions my sense stated that again, that's somehow caused a related to that waterfall. You aren't here to see it, but now you know about it by knowledge, by description. This is one and only one thing that fits that description. And there it is. Now the description here is what Russa calls a definite description. And it's basically a description that fits one thing. An ambiguous description is a description that fits a wide number of things. So waterfalls, right? Waterfalls over five feet high. That's an ambiguous description. That fits a lot of waterfalls, including that one, but a lot more from Niagara Falls to, well, I just don't know that many famous waterfalls. So the ambiguous description doesn't fit at least fits that, but it doesn't fit that uniquely. The definite description fits that uniquely because there's no other waterfall in the Japanese tea gardens. Now I know about this through the same way that you know about this, namely the definite description. Remember, by acquaintance, I don't know that waterfall. By acquaintance, I know my sense data. I know my sense data. By description, I know that waterfall. And the description is basically this, that there is this thing, a waterfall, and we can have a certain set of descriptions about waterfalls. And it's located at the Japanese tea gardens. And there it is. Now Russell's really clear. All knowledge by description must at some point find its origin or find its beginnings and knowledge by acquaintance. So all of my knowledge about waterfalls, all my knowledge by description about people in history, about all the physical sciences, about art, all of that must originate some way, shape, or form by acquaintance. What I get from my senses, what I get from memory, what I get from introspection, what I get from universals, that's by acquaintance. And from that, I get everything else. Here we are back at the waterfall. So there's lots that I know by knowledge by description. I know about Albert Einstein, even though I never met him. I know about, what? I know about the Eiffel Tower, but I never been there. I know about Capitol Building in Washington, DC. Again, I've never been there. There's lots that I know by knowledge by description. But all of it, Russell says, can be reduced to or found, right, or derived from knowledge by acquaintance. So without forecasting too much ahead, I guess some of these examples in there, by knowledge by acquaintance, I'm familiar with sense data. And this sense data is from a teacher at some point that has told me about the Capitol Building being a Washington, DC. And I've been, I've seen pictures of the Capitol Building. I've seen pictures of Washington, DC. I've seen Washington, DC on a map. And I've seen the Capitol Building on a map. Now, by acquaintance, I have all of that, all that sensory input. I also have some general principles about the reliability of teachers and maps and pictures and everything else. And from that reliability, I know by description the Capitol Building. Now, obviously there's gonna be more room for error depending upon the general principles or the sources of the information. Granted, but that doesn't change the kind. Even though you're seeing this waterfall on the computer screen, it is by description that you know about the waterfall, not acquaintance, not acquaintance. By acquaintance, you have the sensory data. Then you have certain general principles involved about the reliability of video cameras and me and everything else. And that altogether gets your knowledge and description of the waterfall, just as I have knowledge by description of the Capitol Building.