Plato's Divided Line
Knowledge Requires Understanding
- The world is constantly changing and nothing is permanent
- If perception is the way you become aware of material objects, it will not by itself produce knowledge
- Objects continually change their properties, so everything you percieve is a new object
- True knowledge involves not just having sensory information, but understanding what is percieved
- Understanding is a process of classifying things as to belonging to certain general types
The Divided Line
- General types or classes are called concepts. ex) this apple is red
Mathematical Objects
The Theory of Forms
Knowledge and Reality
- Presents a grapic description of Plato's Basic metaphysical & epistemological beliefs
- Gives a good idea of Plato's view of reality & how we know it
The Allegory of the Cave
Forms
Plato's Theory of Forms
- highest reality
- highest form of knowing called "understanding"
- Different forms of knowing require different objects to be known
- Imagining requires images, perception requres material objects, reasoning requires mathematical objects, and understanding requires the Forms
- Understanding = highest way of knowing, where as
- Reasoning = where we accept certain axioms as true, and deduce conclusions from them. It's a more imperfect type of knowledge
- Reality has different levels
- Four different ways of knowing must mean there are four different sorts of things known
- Most basic thing to be said about any sort of being = certain "kind" of thing
- Ex) Material objects, mathematical concepts, and forms
- What makes an object a certain "kind" of thing?
- Not a collection of shared sensory properties
- Share the same intelligible structure (a common essence or essential structure) even if they have different sensory properties
- Intelligible structure- not visible, but rather a structure that is understood by the mind
- What plato means by Form- the true nature of a thing
- Forms- set of ideas we use to classify things, and thereby understand them
- Material objects = imperfect copies of their form, defining their type
- Forms collectively make up a system of ideas that plato identifies with the higest type of reality
- Prisoners held in chains in a cave facing the back wall
- Additional people in trenches carrying cardboard cut-outs of objects/people, casting shadows on the back wall
- To the prisoners, these shadows are all they know, they're reality
- Suppose a prisoner breaks away. He sees the people with cardboard cut-outs and realizes the shadows on the wall are just copies of these.
- He then crawls outside at night, and realizes the cardboard cut-outs are copies of these real trees, rocks, etc.
- The next morning, he sees the objects in the sunlight and sees them for what they really are, and realizing what is truly real.
- Ideas and concepts
- ideas provide basis of knowledge
- Third level of reality
- think of concepts as existing a part from any mind that thinks them ( seperate from minds, not dependent)
- Influenced by the Heraclitus, Pythagoras, and Parmenides
- unchanging
- these objects are entities; such as numbers, circles, triangles, other figures, ratios, points, and lines
- Material objects provide opinions
- Concepts are ideal objects; can only be thought
- Most basic beliefs we posses
- Knowledge- reliable knowledge has to be based on facts or inside information
- Reality- distinguish between dreams, hallucinations, and reality
- Basic beliefs about what really exists are called metaphysical beliefs
- study of them is called metaphysics or the philosophy of reality
- Basic beliefs about knowledge are called epistemological beliefs
- study of them is called epistemology or the philosophy of knowledge
Lowest Level of Reality
Next Level of Reality
Plato's Analogy Explained
- Knowing forms and mathematical concepts means knowing everything essential about existence
- Highest degree of wisdom is understanding the Forms
- We do not know the forms through perception, but rather are able to perceive only because we have knowledge of the forms
- We find knowlegde of the forms through "understanding"
- The mind grasps the form by intuition or insight
- How the forms are known
- What occurs when you "get it"
- Plato is suggesting that we might all be like prisoners trapped in our own beliefs
- What we believe to be real is nothing but a world of shadows and appearances, compared to what really exists on a deeper level
- The Allegory of the Cave show us that Plato has accepted the distinction between appearances and reality
- Appearances are real, but like the shadows in the cave, they are just copies of higher reality
Sense Knowledge vs. Intellectual Knowledge
- Sense knowledge gives information only of appearances
- Intellectual knowledge = the true way to reality
- Conceptual knowledge, not just what's perceived by the senses
- Images: various sorts of copies of material object
- (Ex) Images within your mind/dreams, reflection of your face in the water, paintings
- By using imagination, we can't get a deeper understanding of the truth
- we see only a poor copy of material objects; a disortion of what they really are
- Material Objects: are objects that we are aware of
- Copies of mathematical objects
- We precieve objects by their properties
- More real things than their images
Plato
(427-348 BCE)
- considered one of the true giants of philosophy
- Most influential philospher in all of western philosophy
-he invented the Divided line which shows the different levels of knowledge
- his philosophy was the first true system of western philosophy that we have a written record of
Innate Ideas
The Demiurge & The Good
- Sophists believe that knowledge is perception, which is relative
- Plato believes that:
- perception only yields opinion, but perception is not the only knowledge we have
- in the case that sophist's views are correct:
- if what is true is merely what individual people say is true, then anything and everything is true, which means that nothing is true, and that no statements describe how things really are
- we do have objective knowledge- knowledge that is true for all at all times
- there is more than opinion
- Plato says: discovering the forms is not discovering something new
- we are born with knowledge; waiting to be discovered
- these ideas are a part of us from birth; not learned or acquired in any manner
- it is an explanation to "how?"
(ex.) carpenter builds a house (material) accord to an archietectural plan (mathematical)
- Forms exist in ideal world, material objects exist in minds of a person
-could be a copy or a thought
(ex.) Sun
- brings happiness once one posses it
- it is beyond definition in our human concepts; it is unclear
- reincarnation: our souls existed in another world; our true world (a place of happines), called the "Platonic Heaven"