thumbnail of From Socrates To Sartre; #4; Opinion Versus Knowledge
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Oh. The allegory of the cave of humanity being chained in darkness knowing only shadows on the wall wheeling and dealing living out their law ignorance and corruption has haunted the minds of the Western world for 2000 euros. One interpretation of the allegory of Plato himself was anxious to have you make is that it is an allegory of education and that the key to the allegory is that the ascent out of a cave of ignorance and degradation is by education to the truth. What then is the true knowledge which is only to be found by the ascent from the cave to the light of the sun. Plato offers his theory
of the nature of knowledge in the Republic from Section Five hundred nine to the end of Book 6. Socrates is represented as conversing at this point with a glow on one of Plato's brothers and to illustrate his theory of knowledge he gives directions for a seemingly simple diagram. Take a line divided into two on equal parts one to represent the visible Auda the other of the intelligible and divide each pot again in the same proportion with these words. Plato introduces his famous figure of the divided line of knowledge which is his effort to present his theory of knowledge diagrammatic only as the cave presented it allegorical. A vertical line is divided into four segments each of which from the lowest to the highest represents a level of knowledge. Each level of knowledge conjecture understanding reason has its
own objects and its own method for knowing them. The basic division however is between knowledge whose objects are in the intelligible world and opinion whose objects are in the visible world and not to examine the divided line and its levels of knowledge in some detail. Conjecture or imagining represents the lowest rung on the ladder formed by the divided line of knowledge of its objects in the lowest degree of truth. It is the level of knowledge in which mental activity is at a minimum as in the awareness of shadows reflections in water or in mirrors or in smooth shiny surfaces or after images. Other examples of the level of conjecture are optical illusions. Dream images fantasies soft to borderline appearances at the point of waking or of falling asleep. But Plato's references to shadows and to images and illusions Ritu have
many implications. Plato was saying many things at once here. He is saying that the awareness of images is the lowest level of knowledge since images are only shadows of the actual objects known by perception which is a higher level of knowing than imagining. But it is still only opinion not knowledge. Plato seems to be alluding to artists whose paintings or sculptures are as Plato sees them only images shadows copies of actual human beings and other real objects. A still life painting of an apple is only an image of the actual apple. Painters poets sculptors playwrights whether of comedy or tragedy are for Plato. Mirror makers of images fabricators of shadows and illusions of make believe and Plato assigns them and their work to the lowliest level of the divided line of knowledge.
Why does Plato so degrade and devalued the artist Plato was suspicious of all forms of communication which use images such as painting poetry or a play sculpture. Since the mouse is in a democracy are easily influenced and controlled by person of imagery. What do you suppose Plato would have thought of television commercials or of the slick paper magazine ads with sports cars diamonds and round the world ocean cruises. What would he have thought of a growing public relations industry which is in the business of manufacturing images for its customers to present to the public. Plato also feared politicians as skillful image makers. He believed that the softness for their own political purposes were teaching their clients a distorted image of the Athenian Constitution. And most they
presented only a shadow a literate image of the actual Constitution at the present time. A good example of a mere shadow knowledge of our own Constitution occurred in the responses to a recent questionnaire in which many people rejected as illegal a set of statements which turned out to be the Bill of Rights of the Constitution of the United States. The next level on the ascent of the divided line of knowledge is that of the leak which is the perception of actual objects. The level of belief is first of all the level on which there occurs the recognition of things of three dimensional objects visible things like apples people stars dogs cities. This is the level of human knowledge at which the classification and organization of
perceived objects begins. The actual things recognized are grouped together or classified in so far as they are similar as apples are classified as Macintosh. BALDWIN delicious roam Stayman and so forth. But knowledge at the level of the leaf does not grasp the abstract concepts of the objects which are perceived. Does not grasp the bottom this concept of the apple which identifies the unchanging characteristics of each species of Apple. The leaf which has its source in the perception by the senses of actual objects is thus in secure. It is not based upon abstract truths or principles which are unchanging and which would give the Fama what the scientific botanist has true knowledge on the basis of which he could rationally classify and predict explain and
systematize what he knows. The point that Plato is trying to make us see is that perception of objects by the senses in the visible world can never give us true knowledge. And for two reasons. First what can be known by the senses he tells us is only of the world of flux. The world of Heraclitus. The world of particular things that are in the process of change. What we know at the level of the least is always subject to change since we know only what we perceive in the visible world which is the world of continual change. Since the features we perceive trees and horses and people and cities and chairs do have are continually changing. We can never be sure of our own knowledge of them. We can only know how things seem to be on the basis of our perception of them not how they
actually are in fact. So as Plato We do not have knowledge at this level but only opinion. It is however a true opinion since it does recognize actual objects and those provide rough classifications and rough predictions. Plato was saying that this is the level on which the common sense mind the mind of the Man In The Street operates. It is therefore to be distinguished from the level of conjecture which knows only images and shadows and which can only be called a false opinion. Plato was also trying to give us a second reason. That sense perception can never give us true knowledge. This second reason is that knowledge derived from the senses can never give us a general universal unchanging and abstract truth of the intelligible world. Rather the senses going to give us only
particularly changing and concrete observations of this house that dog that tree of the visible world. Plato is thus maintaining that sense perception which is how we know on the level of the leaves cannot give us certainty in knowledge or unchanging universal truths about reality brought certainty and a universal truth about reality. Precisely what true knowledge must provide. What then is true knowledge. And how can true knowledge be reached. The pressure of these questions is now intensifying for Socrates friends and add a mantis. As Plato describes the mounting tension of the ladder of knowledge. And we too feel this tension as we climb the ladder and
look back. At the World of every day we leave based on an examined common sense experience of how things seem. Even farther down below us now. Is the world of mirror images of shadows and fantasies of the world a powerful but the sept of illusions fabricated by artists poets dramatists mis makers and political demagogues con men like the notorious Sophos. As Plato saw them with Plato. We reject these lower levels of thinking and what they think about and we reject the kind of life that is lived by human beings on these low levels of knowledge. And so we asked send to the third level of the ladder of knowledge. The level of rational understanding or intellect. The change is from belief
in the concrete changing particularly objects of perception. To the rational understanding of abstract unchanging universal concepts which are the objects known by intellect whereas the traditional Fama on the level of belief makes a rough classification of particular apples by perceiving their actual different shapes sizes colors and textures. The scientific botanist has knowledge of the precise characteristics of each species of Apple. Also he has knowledge of the principles of morphology concerning the reproductive parts of the apple blossom and he has knowledge of the principles of genetics concerning the genes of the different species of apples. And he has knowledge also of techniques for the improvement of the apple species. The change from the knowledge of the traditional unscientific Fama to the scientific botanist. This is the change we have brought about by
sending from belief to rational understanding and in making this ascent to the third level of the ladder of knowledge. We have come now to grasp the significance of the divided line. For on the third level on which we have now arrived we have crossed over the major division of the divided line of knowledge we have entered the intelligible world. We have left the cave of every day beliefs and artistic fantasies and we have struggled upward into the light of the sun. We have left behind the concrete objects of the visible world the everyday objects of the prisoners in the cave. But what kind of objects are we ascending to in the light of the sun. What all objects do we know by intellect when we cross over the line into the intelligible world. Why does Ansar is that the object which we know by intellect or rational understanding on the third
level of knowledge are the true concepts to which we have already made reference. In contrast to the objects of belief we have already noted that whereas the objects of perception are concrete the objects of intellect are abstract whereas the objects of perception are particular things the objects of intellect general or universal concepts. And whereas the objects of perception are changeable in process in how in flux the objects of intellect are unchanging in Parliament a dn eternal immutability. Plato has a special name for such concepts. He calls them forms or ideas. But how do such concepts give us true knowledge. What is their relation to the concrete objects of perception. How many such concepts are there. How can we know them. How can we prove that they are eternally true.
In asking these questions we have come face to face with Plato's famous theory of ideas. His famous theory of forms which is his most creative and influential philosophical contribution and is the central theme of his entire philosophy. Since I have crossed over into the intelligible world whose objects are the forms Let us pause before as sending to the highest levels of the divided line and examined the Platonic Theory of Forms. Or Plato concepts such as the concept of a circle a triangle beauty justice as well as the concepts that make up our everyday vocabulary such as house yellow man have two crucial functions. The first of these functions is that they make it possible for us to know the actual world of things as well as the objects of mathematics and the sciences and philosophy. Their second function is
that they enable us to evaluate and to criticize all these objects first to abstract concepts enable us to have a knowledge of all objects the objects both of the visible world and of the intelligible world. Plato's point is that to think or to communicate at all requires the use of concepts. Concepts are the means by which the universe is made intelligible. The simplest statement there is a man uses the concept man. There is an Apple uses the concept Apple for anything that can be named horse triangle and there just is. There is a concept and to each concept there corresponds its eternal form. And now we can define an idea or form. For Plato the forms are the object of universal and immutable set of qualities which define concepts.
More simply put forms define our concepts forms our ideas of the eternal and immutable definitions of our concepts. For example the form of the concept triangle is that it is a plane figure bounded by three intersecting lines with three internal angles whose son is 180 degrees. This form is shared by the entire class of triangles that is by all the triangles that ever have been or will be drawn. Forms or ideas of the eternal and immutable absolutely true definitions of concepts such as beauty triangle. Form specifies the qualities which any particularly any particularly beautiful object or any particularly triangle must have in order to be considered a man or a beautiful or a
triangle. But also the forms are real. They are independently existing entities. They have independent reality in the realm of the intelligible. For particular things such as man or trying goals they are real only to the extent that they measure up to the eternal truth of the form. Plato sometimes speaks of the forms as essences meaning that they constitute the essence or essential substance of things. We can now understand that the forms our ideas are not mere ideas for Plato. They are not subjective merely mental entities confined to human minds by idea we ordinarily mean any particularly. Think of something in my consciousness something private to my mind. Just the contrary of this. The forms only are ideas or
mental entities for Plato. Of all the components that make up reality the forms have the greatest claim to reality the most real for Plato. They are the essential substance of any reality or whatever is real enough to be thought about. The changing things of the visible world relate to the immutable forms of the intelligible world as imperfect copies of the forms. We can see now how it is that the forms make true knowledge possible. As we have already discovered true knowledge must meet two requirements. It must be immutable unchanging and unchangeable. And it must be about what is real knowledge based upon sense perception at the level of belief was we found out. Neither are unchanging because of its insecurity nor about the real since it was knowledge of the flux. By contrast knowledge based upon the forms will
be immutable and unchanging since the forms are immutable. And knowledge based upon the forms will be knowledge of the real since the forms constitute essential reality. And now briefly to examine the second function of the forms that is there are evaluated and critical functions of pure and eternal forms. Define our concepts by the same token they establish standards or ideals by which to evaluate the world of things and flux in the world of flux. Things are always in a state of change. They are coming into existence or passing away and the qualities of the forms. For example the case of the apple are very imperfectly copied in the concrete wormhole the apple. Similarly no actual lines that we can draw will meet the standard of the form A quality. No
to learn things in the visible world are ever perfectly equal. Nothing in the visible world is ever perfect in its kind. Only the pure or intelligible immutable forms which establish the qualities defining each specific concept whiteness. Justice circle triangle only the pure forms perfect. As we shall see Plato will make his most striking use of the Evaluate of or normative function of the forms with regard to the ethical and political forms of goodness and justice. Whereas to most of us as to the softness. Justice is relative. On Plato's theory of forms the form of justice is like all other forms immutable and eternal. What a present day socialist or communist. Accept this and now to return to the ladder of knowledge. The
third level of knowledge is as we have already seen the level of rational understanding or intellect. Plato was here describing the kind of knowledge which characterizes mathematics and the sciences. The objects of the mathematicians knowledge off forms forms such as triangles circles and other mathematical objects. These forms known by the mathematicians of rational understanding or intellect and they are objectively universal and immutable. These forms are unchanging and eternal. The area of a circle is always squared. But the mathematicians knowledge does have deficiencies. It is still tied to the visible world by its use of diagrams in the proofs of geometry. The well-known figures of school is triangles circles. A second limitation of knowledge at this level is that it does not examine or prove its own assumptions and thus this knowledge
remains hypothetical or conditioned rather than being based upon first principles which are proven to be true. Natural Sciences like an automatic CE have as their object. The forms with which these sciences deal. For example Plato thought the forms of earth air fire water and although the natural sciences like mathematics provide knowledge of the forms both mathematics and the sciences are limited in three respects. They rest upon an examined first principles. They are tied to examples particular instances from the visible world and they are piecemeal fragmentary. They fail to show the relations of the sciences to one another. We ascend to the fourth and highest level of knowledge. Pure Reason on this level. The mind uses the
method of dialectic which in this context means the science which studies the forms dialectic has been called the programming science of all sciences. Here the true philosopher has come into his own realm. He moves toward knowledge of the forms by the activity of his reason and through the use of dialectic as his method the method of analyzing the essences all forms of all things in the universe and seeing their relationship to one another. And in the dialogue called the symposium Plato shows that the philosopher moves toward the eternal and pure forms out of the power of His love desire Eros which leads him from the love of a beautiful body to the love of all beautiful things. And then to the love of the beauty of the mind as greater than the beauty of the body. And drawing toward and contemplating the vast sea of beauty Plato says
at last the vision is revealed to him of a single science which is the science of beauty everywhere. So in the Republic the philosopher uses dialectic to take up the unfinished task of the third level of knowledge and establishes on the Fourth Level true first principles for mathematics and for the sciences without employing diagrams or particular things from the visible world. Secondly dialectic unifies the isolated fragmentary unrelated sciences and mathematics into a single systematic unity. And thirdly dialectic identifies the entire range and variety of forms from forms of lowly things such as apples and dogs relations such as quality and similarity artefacts manmade things such as beds and shares
values such as beauty and goodness and justice by the power of dialectic. The philosopher not only identifies all these forms and establishes the truth. What dialectic also organizes all the forms into a single rational structured order of truth and value. The forms constitute a hierarchical structure. A pyramid from the many least universal to the few most universal from the most concrete to the most abstract from the forms of mud and dirt to the forms of identity and difference. And finally in the US sent to the truth the philosopher by the power of love of the good transcends this rational pyramid. This ordered structure of the hierarchy of forms and reaches the idea of the good. Plato compares the ideal of the good to the sun whose light makes the concrete things of the world visible and so is
the source of their life and growth and value. In the idea of the good Plato has given expression to a vision of an absolute source of truth and goodness. The idea of the good is the source of the truth and value of all the other ideas all forms the ideal of the good is the source of the world's moral purpose with the essense to the ideal of the good and absolute one of truth and goodness. Plato prepared the way for the Christian God like the God of Christianity the ideal of the good is the supremum value. It is the source of all value the ideal of the good is Plato's conception of the absolute the perfect principle of all reality and of all value and of all truth. For a thousand years when Christians thought of God they envisage the ass sent through the power of reason and the power of love. To Plato's idea of the good.
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From Socrates To Sartre
Episode Number
Opinion Versus Knowledge
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Maryland Public Television
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Maryland Public Television (Owings Mills, Maryland)
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Episode Description
#4: Plato III: Theory of Knowledge - Opinion Verses Knowledge What is true knowledge and how is it reached? Plato's theory of knowledge. The Divided Line: diagram of four states of development of knowledge. Plato's theory of ideas. The idea of the Good. Contemporary significance of Plato's rationalistic theory of knowledge. Implication for art, common sense, religion, empirical science, mathematics. The meaning of "dialectic." The idea of the Good as Christian symbolism.
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Copyright Holder: MPT
Host: Thelma Z. Lavine, Ph.D.
Producing Organization: Maryland Public Television
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Maryland Public Television
Identifier: 36572.0 (MPT)
Format: Digital Betacam
Generation: Master
Duration: 00:30:00?
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