plato and the forms according to plato, common sense is wrong. we do not sense the world as it...
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Plato and the Forms
• According to Plato, common sense is wrong. We do not sense the world as it really is.• The senses present the world in a confused way.•The mind ‘sees deeper’. It sees the true natures of things.•Plato explained this with the Allegory of the Cave
The analogy of the cave:
ordinary mortals see only the shadows of
reality.
The real things – forms – exist
outside.
The forms project their
shadows onto the cave wall…
…just as the forms are somehow
dimly projected into
real things.
The Forms
• Reality contains forms. They are the timeless and changeless natures of things.
• They contrast with particular things in the ordinary world (of appearances) which are constantly changing.
• But why believe this story? How do acquire knowledge?
So, beauty can’t belong to the
world open to the senses.
Plato, Change and Sameness
But there is nevertheless
something stable here: beauty itself. These beautiful things
must ‘share’ it to be all called beautiful.
Beauty itself cannot change or be
destroyed: we could still talk and think
about it in the absence of beautiful things.
Beauty belongs in a
different realm to the realm of appearances
and it is reason that
gives us access to it.
The world shows signs of both stability and change,
difference and plurality.
A beautiful painting must be created, may be adjusted and may be destroyed: all
examples of change.
Two beautiful pictures may look very different
yet both be beautiful.
There can be many beautiful things.
The senses only reveal a world of
change.
The Imperfection Argument
We know many truths about
circles
Area = πr2
360o in a circle.
But no circles we see or draw
are perfect.
So, our knowledge must
be of some perfect circle - the Form of the circle.
CircleMagnified section of
circumference
Ideal geometrical circles have unjagged circumferences with no width and are infinitely thin.
And since it can’t be sensed, it must
be grasped by reason.
The Knowledge Argument
Knowledge is of truths - if you know something, it can’t
be false.
In the world of appearances, everything is
changing.
It is sunny now but it might not be later.
I cannot therefore know it is sunny.
I can merely have the opinion or believe that it
is.
Knowledge must be of changeless things…
…the forms…
…which cannot exist in the world of
appearances accessible to my senses …
…and so exist in a separate realm
accessible to reason.
The “One Over Many” Argument
The “one over many” argument: if x and y are badgers, there must be something – the
Form of the badger – that they have in common. They both “participate in” the Form of
the badger.
What makes something the kind of thing it is?
What makes a badger a badger?
What makes two things members of the same kind?
What makes these two things badgers?
Participation
World of appearances World of forms
Form (archetype) of the badger
There must be some explanation for why things belong in kinds.
These days, philosophers talk of universals instead of forms.
The Form of a badger is not present where the badgers are but exists in a different realm.
The universal badger exists in each and every badger. It is quite unlike an ordinary object, as an object can be only in one place at any one time. Objects are a type of particular. But the universal
exists in many places at once – it is repeated throughout its instantiations – and hence is called a
universal.
Fundamentally, however, we’re talking about the same thing – an entity that makes a particular belong to a
kind or makes it the kind of thing it is.
Aristotle thought forms were immanent – located in the physical realm where their instantiations are (he would have understood them as universals) whereas Plato
thought they were transcendental – located in another realm altogether.
Why study the forms?
This is useful: we like beautiful things and we want to praise acts of
goodness and punish badness.
He was searching for the nature or essence or, to use Plato’s word, the form of beauty.
But we also want to go deeper and ask what it is that we recognise.
We recognise examples of beauty and goodness.
Socrates would ask, “What is beauty? Truth? Justice?”
There is obviously a practical angle. People differ over what they think is right.
People are sometimes uncertain. We need to remedy this.
But there is also a purely philosophical angle: simply finding out the nature of the
reality we inhabit.
The Context Argument (*)
Something F in one context may
not be F in another.
Picture A may be beautiful in relation
to picture B...
Context 1 Context 2
...but not in relation to picture C.
Since the painting can be beautiful and not
beautiful, it can't provide us with a definition of
what is beautiful.
Whatever beauty is, it can't fail to be beautiful. Since any thing that we find beautiful could fail to be beautiful in another context, we
can't simply collect beautiful things together and hope that they will share some simple
sensory property that we can identify as the property of being
beautiful.
We have to look for the Form of the beautiful or beauty: the thing
that makes beautiful things beautiful. It is the essence of
beauty. But it cannot be detected by the senses, only reason. Why? Take a beautiful painting. In one context beautiful, in another not.
But nothing about how the painting appears changes. So,
we're looking in the wrong place if we look for beauty amongst
perceptible properties.
Plato and the Forms: Summary
Reason gives us knowledge of the Forms (universals)–
the essences of things.
The Imperfection Argument: No perfect circle can exist in the sensible world, only
approximations. No actual circle can be infinitely thin and perfectly curved.
The Knowledge/Change Argument:
the Forms are unchanging. Sensory experience reveals a
changing world. So, the Forms are non-sensible.
The Context Argument:
whether a painting is beautiful or not varies with the context but its sensible features do not. So, the Forms can’t be sensible.
Before we were born, our souls
lived in the world of Forms.
In this embodied life, our knowledge of the forms is buried
and must be unearthed by exercising reason – doing
philosophy.
The Forms cannot be detected with the senses
but only with reason.
One Over Many:If x and y are both F, then there must be something, F, that
they have in common.
Knowledge of the forms: Meno and the Slave-boy
How do we know about the form? Because we have
innate ideas, gained from when our souls existed in
the world of forms.
If ABCD is a square and AD is 2 feet, then the area
is……4 ft2
So, if AD = DL, then AL= ?…4ft.
And so the area of ALKJ is…?…8 ft2
This shows that the boy knew all
along the relevant principles of
geometry.
Plato demonstrates this by getting Meno’s slave
boy to prove a mathematical theorem.
No – for ABCD is 4ft2 and there are how
many such squares in ALKJ?Four.
So the area is…?16ft2
Now, BDNM is composed of four parts each of which has what area? 2ft2
So, the area of BDNM is..? 8ft2
By asking a series of questions, Socrates gets the slave boy to work out the area of two squares
When we are born, our soul ‘forgets’ the ideas and they need to be recollected.
Problem: Learning or recollecting?
Was Socrates asking fair questions?
Or was he giving the boy the right answers disguised as questions?
We might defend Plato thus.
Sometimes, all a teacher can do is get you to work
through examples until you ‘get it’ with a flash of understanding.
For example, it might be that you suddenly see how
to calculate a percentage…
…or understand an argument,
such as the ones we’ve looked at
here.
Problem: Forms can’t be sensed.
Common sense tells us that we should believe
our eyes.
But we can’t sense the forms.
We can’t sense God or numbers or
atoms either.
We believe in them as they provide the best
explanation of the world we can sense.
So that is how we should judge whether to
believe in forms or not.
…We must ask whether there’s a
better explanation.
Problem: Will appearance do?
Socrates tells us there is a form of beauty but not of
hair.
There’s no such thing as perfect
hair!
But then how do we identify
hair?
Examples of hair are just like examples of beautiful
things: they differ from one another, change and can
be destroyed
Socrates tells us that appearances
will do.
So, we identify hair on the basis of
(perhaps) what it is made out of, what it looks like, where
it is found.
But why not say the same about beautiful
things?
If we could, we wouldn’t need to say that there is beauty
itself as a strange thing in a realm of forms.
Question: Will ideas do?
Why don’t we say that there isn’t really a perfect
circle ‘out there’…
…it’s just an idea in my mind.
But what about when you think of
it?
It is an idea in
your mind as well.
But what guarantees we have the same
idea?
Perhaps nothing! Just as people have different ideas
about what is right and wrong, why not about maths
and geometry?
Question: Will ideas do?
This won’t work.
…Every people that have ever thought about maths have arrived at the same ideas about numbers and
shapes. Surely this shows there’s just one
true set of ideas.
It is inconceivable
that 2+2=5. Try making it work!
If 2+2=5, then 2=3? And 0=1???
Even babies have some
innate mathematical
skills!
If by putting 2 by 2 I get 5, I could fill the
universe!
And I could change the past by simply thinking about two people I met
yesterday alongside two other people I met yesterday – I could now make a
fifth person appear then!