 So, to this point in our course, we've seen lots of attempts, you know, starting with Thaley's, trying to answer this question, you know, what is this thing? Trying to understand what it is. We've even seen answers from, you know, some of the sofas that, you know, it's whatever you want it to be, right? Ranging from this reality that's independent of the mind to which our mind was conformed and not the other way around to, you know, just make it whatever you want and it is that. So, what do we can argue? Well, Plato is still grappling with this question, he's trying to really deal with two questions that, you know, are on the top of our minds really, right? And the first is, you have to explain that a thing exists, right? So I'm walking through this park right now and I'm walking past these trees and I'm not thinking to myself, wow, it's really kind of neat, these trees just popped into existence the minute that I am here. No, I mean, there's some reason, there's some account for why these trees are here before my arrival, they didn't just pop up right now and they didn't just pop up, they came from something. Yes, that's the first question you ask is, I have to explain is that a thing exists? How did it get to be here? What brought it into existence? What's it composed of? What was the causal chain? What's its history? Okay. The second question is what a thing is? That something, you know, explaining that something comes into existence or that something is now existing, okay, that's one thing, but telling us what it is after that is something else. Now we say these are trees, all right. The question of that the tree exists, can be explained, right, we can do a real good job of this talking about, you know, the seeds of the trees, the germination of the ground, water, soil, nutrients, the gases that are in the atmosphere and, you know, that in fact, how it interacts with the rest of the environment, okay, that, you know, that's the that of the tree's existence. The what is what it means to be a tree? There's something of what it means to be a tree and for me to be human and there's a difference between those two things and what it means to be ground and air and water and animal and everything else. Now Plato is trying to answer both questions, is trying to explain that and trying to explain the existence of every individual thing and what it is, I mean, that you're trying to explain that it exists and what is its existence by appealing to form. So Plato's first step and trying to give this answer to the, you know, trying to explain the existence of everything and what it means or the whatness of everything, the essence of everything by, you know, appealing to form is to first provide a refutation against relativism. Now relativism, you know, if we're going to just kind of simply state it, is the assertion that a proposition P is true when and only when a person believes it. So this is the idea, if you want to account for truth, you want to know what's true to ask what people believe, right? This is just what makes a proposition true is the fact that a person believes it. We make the truth, okay. Well, relativism has some issues here because as a matter of fact, not everybody believes this, right? Plato, Socrates, Aristotle, a host of philosophers through history, a host of people today, think that this is false. Now plenty of people thought it was true. Okay, that's not the problem though. The problem is that plenty of people have thought that it's false, that a proposition is true when and only when a person believes it. There is such a thing as being mistaken. If relativism is true, nobody's ever mistaken, right? But there is such a thing as being mistaken. So, yeah, you know, plenty of people have argued that, well, it's false that a proposition is true when and only when a person believes it. Now, merits of their arguments aside, as a matter of fact, they believe this is false. Okay, well, if a proposition is true when and only when a person believes it, and as a matter of fact, some people believe it's false that a proposition is true when and only when a person believes it, well, this means that there are some people with at least one, excuse me, there's at least one truth that's true regardless of people believe it, you know, namely, these philosophers, and these philosophers believe that it's false, that a proposition is true when and only when a person believes it. So, yeah, this is kind of what's interesting about relativism, say, you know, we, our beliefs make the truth, but some people believe that that's false. So, okay, they're mistaken. There's at least one true whether they believe it or not. Well, if there's a truth, whether somebody believes it or not, well, then relativism is false, right? Relativism asserts that what makes something true is our beliefs. But here's a belief or here's something that's true, and here's something that's true and people don't believe it. That's kind of a problem for relativism. It rejects itself, given all the relevant evidence, right? Now, you know, there's lots of ways to look at relativism here and, you know, lots of ways to argue against it. You know, the little passage in the text goes about one way and you may walk over that in class, but, you know, this is at least his first glance at why Socrates and Plato reject relativism, because at the end of the day, you know, it rejects itself. So the first step that Plato takes is rejecting relativism. The second, yeah, so this, you know, this establishes that there is some objective truth out there, right? This isn't just anything that you want it to be. The second step is to understand the source of our knowledge. Now, we might be tempted to think that the source of all our knowledge is perception, right? What we see, hear, taste, touch, smell. Now, the assertion that the source of all knowledge is perception, what we get from experiences, is called empiricism. Empiricism. Empiricism is not being a fan of Darth Vader, right? Empiricism is the claim that all of our knowledge, the source of all our knowledge, is perception. Now, Plato rejects this idea. What Plato endorses is what's today called rationalism. Now, rationalism asserts that at least some of our knowledge is not from experience. At least some of our knowledge is not from experience. Plato takes a pretty heavy version of rationalism. He's going to say the source of all real knowledge is not from experience at all. He takes a pretty heavy version here, but you know, bear with them. Okay. So, at least just hear him out before you say, whoa, Plato, come on, that's crazy. All right. So, how does this go about? Well, as we saw with a lot of philosophers from previous readings, he looks at change. Change. Now, it doesn't look like it right now, but this creek bed has gone through a lot of changes. At one point, there was water flowing through here. There's not water flowing through here now. There was probably, or maybe there's more soil on the ground that's been washed away by floodwaters or creek waters. Some of the vegetation has lost its leaves, but you know, that's the season for it. The leaves will grow back. Some of the vegetation wasn't always here. Some, you know, it grew up from the ground. Some of it will disappear, right? It'll die and wither away and decompose and provide the fuel for the next line of vegetation. This won't always look like. I mean, this whole area didn't always look like this. You may or may not know this, but this whole area, way, way back. We talked about thousands of years. It was once covered in water. We've seen the fossil evidence for that. Some day, maybe to be covered in water again, or maybe all the water will, you know, be somehow destroyed and this will just be a desert landscape after a while. Whatever. The point being that, you know, while it looks pretty stable now, this goes through a lot of changes. And, you know, as it goes through changes, it becomes one thing or another. Alright, so, you know, there's a tree right over there. It's kind of big at this point is what 20, well, big compared to me anyway. You know, it's what, 20 feet tall? It wasn't always 20 feet tall. It started out as, you know, some kind of seed, an acorn. It sprouted through the ground, right? It grew leaves, it grew more branches, it grew bark. Right now it's lost its leaves, but it'll grow leaves back. So as it, you know, goes from the seed up to that, it's becoming something, right? The acorn, that seed, the little sproutling, is becoming something. It's becoming that tree. Well, if it's becoming something, right? If it's going through changes, what it is, is not just the changes, right? If all that exists are the changes, then it's not becoming anything, right? Whatever was there is gone and a new thing is in its place. And whatever that is, is gone and a new thing is in its place. And then that's gone. And until finally we have this, right? But that's just the latest thing at the end of a succession of a bunch of things. Okay. But, you know, we don't think that. We don't look at an acorn and say, oh, well, soon this, you know, there, this will be nothing and something else will take its place miraculously. No, no, we say that it's becoming a tree. Okay. So, whatever a thing is, you know, whatever a thing is, right, is not the changes. If it's becoming, it's becoming something. It's becoming something. You were a little infant and you went through a lot of changes. Well, you're not identical to the changes. If all you are are the changes, you don't exist for very long. We've seen this with Heraclitus. But you're becoming something. So, whatever you are is not identical to the changes. It's not just the changes. I've grown from, you know, 10 inches or so to 60 inches, right? That's a lot of changes. I've grown from 10 pounds to more pounds that I like to admit. I even had blonde hair when I was a little boy. I was a little boy. I had blonde hair. Now, what we only perceive changes, right? We only perceive changes. Changes are reflected by the causal interactions around us. Light, sound, smell, or sight, touch, smell, sound, all that. That's the content of our perceptions. We perceive only changes. When we look at an acorn, right, when it's first planted in the ground, we don't also perceive the tree it's going to become. And when we look at the tree, we don't perceive the dried out husk that it's going to become. We also don't currently perceive the acorn, right? We don't perceive all of that. When we look at each other, I can't look at your baby picture by looking at you. So, whatever we perceive, we perceive only changes. Well, that means, you know, since changes are not identical to the thing, they're not what a thing is, that means that we don't perceive what a thing is. What a thing is, its essence, its definition, its meaning is not given through perception. When I look at something, I don't see its essence. I might see it. I see its color. I might even see its shape, the contours of its edges. Okay, right, we'll grant that to see the contour of its edges, but not what a thing is. Well, if perception gives us real knowledge, I mean, if perception gives us knowledge, perception gives us knowledge at all for Plato, perception gives us knowledge at all, and perception will tell us what a thing is, its essence. Heck, perception doesn't even tell you where a thing comes from or doesn't even explain where it comes from, right? It doesn't answer either one of those questions. Well, perception doesn't do this. Perception doesn't tell us what a thing is. So, perception is not the source of knowledge. Now, either it's perception or it's something else. In this point, we're only considering perception or reason. Well, we might call what identifies conceptual knowledge, knowledge of essences, right? All right, well, if our choices are reason or perception, conceptual knowledge or perception, abstract knowledge, knowledge of universals, or perception, well, and perception of particulars, and perception doesn't do it, then our knowledge has to come from reason. That means our knowledge of what things are for Plato, our knowledge of what things are is not from perception. So, the question is, where does this knowledge, this knowledge by reason, where does it come from? How do we have it? And Plato's answer is going to sound a little different. So, I've said that Plato's going to explain all of this or account for all of this by appealing to form. That's probably going to help at least a little bit to understand what he's talking about. But the way to understand what he's talking about is to start first with what we experience with our perceptions. And form is not that, right? So, as we said before, perception is not knowledge. Reason is knowledge. So, what does perception give us? What is perception like? Well, with perception, I see the particulars, the individual things. I see this bush, this bush. I see that tree, that rock, that grass, right? That particular organism of grass, that particular tree, this particular shrub. Perception gives me the particular, or reason gives me the universal, gives me the essence. This is the particular. The form, the essence, is what all these particulars have in common. Now, you might think, well, I've seen one tree, I've seen them all. No, that's not true, because trees look different from each other. Or even, let's take this, sunglasses, right? All right, this is a particular pair of sunglasses. You see this, but you don't see all sunglasses. You probably can't conceive of all sunglasses. This is a particular. But what they all have in common is the universal, that's the essence. Now, this is made of plastic. The lenses are made of plastic. The arms are made of plastic. Some lenses are made of glass. Some frames are made of metal. You see this particular shape, it's kind of long and has a corner at the ends of it. Some sunglasses are perfectly circular. Some sunglasses are more square. These are kind of dark gray or black. Some are multicolor, right? Some dark blue or blue. Some are mirrored. You know, there's a whole variety of shapes to sunglasses, a whole variety of colors to sunglasses. You haven't seen all of them. Heck, you can't conceive of all of them, right? We don't know what the sunglasses of the future are going to look like. We don't know what they'll be made of. All right. But you know the universal sunglasses. You can look at this and say, yeah, these are pairs of sunglasses. This is, you know, sunglasses are not a hat. Sunglasses are not a shirt. You can distinguish sunglasses from regular glasses, right? So the point of that being is you perceive the particular thing. You don't perceive the essence universal. That you have through reason. So that's the first thing is a distinction between the particular and the universal. The form is the universal. The form is not the reason. All right. This is also the difference between a subjective experience and objective knowledge, right? So perception is subjective. I have my perceptions. You have yours. They don't look alike. Even if you're standing in the same room, look at the same thing. There would be some difference. You know, as, you know, as I've probably mentioned before, I'm slightly colorblind. I can't see as many colors as you do. The color spectrum is going to look different to you than to me. Even our experiences, our memories, our, how we've encountered different things is going to change how we perceive a thing. Somebody who's afraid of dogs is going to look at dogs much differently than other, that people who are not afraid of dogs. So perception, knowledge of the particular, right? The particular experience, that's subjective. Form, the essence, the universal, that's objective. That doesn't change depending on who's looking at it. Perceptions are all subjective. Form is objective. All right. In addition to that, you know, we can contrast forms to the particular things even more. These particular things come and go, right? This tree did not always exist. And then at some point, it will cease to exist. This creek bed at one point didn't exist. At some point, it will cease to exist. But the form, the essence of creeks, the form, the essence of trees will always exist, right? The particular things are temporal. The forms are eternal. So to kind of summarize this, form is known through reason. The particular things, the appearances are known through perceptions. Form is objective. The perceptions are subjective. The particular things are temporary. Heck, perceptions are temporary. The form is eternal. So this raises the very interesting question. Forms are eternal. They're not known through perception. They're objective. How do we know about the forms? So Plato's given us form. Form is eternal. It's objective. It's the universal. It's known through reason, not perceptions. We never see form. Well, if we never see it, how do we know it? Well, Plato says, look, I mean, look what's happening here. You know what goodness is, right? You look at particular actions and you say, well, that's good and that's bad. If I were to randomly walk around and start slapping people across the faces, well, that's bad. That's wrong. You can't do that. You know what shapes are or triangles are. You know what triangles are. You can recognize different triangles without ever seeing all triangles. You have that knowledge. You can look at different figures and say, well, that's not a triangle, right? You haven't even seen all shapes and you could spot the difference between a triangle and a square and a hexagon and everything else. You know what equals is, right? If I have two sticks here. Okay, here we go. Two sticks. You know, they are not equal, right? They're not equal length. They're not even equal width. You can look at that. But, you know, equals doesn't have a color. Equals doesn't have a color. There isn't some color that's shining between these two things that says not equals, right? Equals is a concept. You haven't seen all the twigs in this park and compare them to one another to find equals and unequals and then you'll say, well, this one belongs in the equals line. You know what equals is, even though you haven't seen all instances of equal links and all instances of unequal links, you have this knowledge independent of experience. But, you know, even Plato's not going to doubt that you have experiences that you have perceptions. Okay. And perceptions are what you have through your body, through your eyes, through your nose, your mouth, your ears, your skin. Those are your perceptions, the senses. That's temporal. Your knowledge of the forms, then, of these essences has to then come from the eternal. You know, for Plato, our knowledge of the forms, we have this knowledge of the forms because we, at some point, existed with them without a body. We existed with them without a body. We had some kind of eternal existence or at least non-temporal existence, non-physical existence with the forms. The process of birth was very traumatic. So, we spend the rest of our life recollecting the forms. These copies of the forms, these mere, you know, poor shades of the forms remind us of them. Okay. We recollect the forms through this process of observation. But the knowledge of the forms was always there. All right. Well, you know, whether you accept Plato's account or not, there is some sense in which you may not necessarily recollect the forms, but we discover them. We discover them. You know, looking at triangles, we discovered all kinds of things about triangles. We didn't create these truths about triangles. We didn't decide that the sum of the interior angles of a triangle will be 180 degrees. We found that. We found that. That was discovered, not made. We discovered that the sum of the interior angles of a square are 360 degrees. We didn't create that. We discovered that. So, you know, maybe you'll accept Plato's account. Maybe not, right? As far as how we know about the forms. But it is really hard to deny that we do discover these truths. We don't get to decide what they are. I can decide what a unicorn is, or a leprechaun, or an elf, or a garble, or a wobble, or, you know, I'm going to make a new creature. It's, you know, a trinome. Trinomes hide behind trees, and wherever you look, you know, they're always, they're like really fast, right? So, I'm looking around, they always hide behind a tree. I can make that up. I can't make the sum of the interior angles of a square be 20 degrees. Can't do it. Okay. So, again, whether you buy Plato's account of existence with the forms before a physical body or not, there's still some sense of which we have to contend with this idea that the forms are discovered. They're not made. All right. Now, what Plato has given us here is a view of reality that's contrasted to what we could call materialism. Materialism is the view that the only thing that exists are material or physical objects. Right. So, hearkening back to the distinction between the material and the form will give into us about Pythagoras. The materialists could say the only thing that exists are material objects. There is no form. There is no form. All right. Now, Plato's view, well, it's often just called Platonism. Right. It's the view that there's physical objects, material objects, and form. Right. There's a view that it's that there's particular things and universal things. Right. Both these things are real. They both don't exist in the same way, but they're both real. Now, the book, the text that I gave you calls this idealism. Don't call it idealism. That's something else. It's Platonism. Right. Just scratch out idealism, put in Platonism. Right. It's the view that there are particular objects and universals. Both these things are real. So, we're going to look at this more, we look at the distinction between materialism and Platonism more through the course of the semester and see different philosophers try to grasp with this. And I also want to point out, again, what Plato's given us is called rationalism. Rationalism is a view that at least some knowledge is not empirical. And this is contrasted to empiricism. And that's the view that all knowledge, the source of all knowledge is empirical. Right. That's empiricism. So, Plato's told us about form. And what he's told us is not only the what of this tree is form, right. This tree is a particular thing. And the what of it is its form. But he also says the that of this tree, that is the explaining that it exists is also form. Because as I said, as we pointed out, these are particular things. These come and go. But the forms are eternal. That means that the form is more real than that tree. And when you understand form, you understand reality better. You want to understand that tree? Don't look at that tree. Look at its form. To understand all trees, look at its form. And when you really start to understand these forms, and you understand that the forms of these things are what all these things have in common, the next step is to ask, what do all forms have in common? What is it that all these particular things and forms have in common? Because they all exist. It's all good, goodness. So you're working way up to what everything has in common. And what everything has in common for Plato is goodness, is being itself, existence, exist. And when you understand that, you understand everything else. This, for Plato, is wisdom to understand being, goodness, truth.