immanual kant

IMMANUAL KANTIMMANUAL KANT

The Copernican Revolution in Philosophy

The Copernican Revolution in Philosophy



Kant was one of the first to truly appreciate Hume’s skeptical

dilemma.


Hume had demonstrated that many of our basic common

sense beliefs cannot be justified.


Common Sense Beliefs:1. There is an independent

physical world. (Material substance exists.)

2. I exist.

3. Every event is caused.

4. Causal laws will not change.


Hume had shown that none of these statements are analytic truths, and none of them are a

posteriori truths.

Hume insists that every truth is either an analytic a priori truth, or a synthetic a posteriori truth.


Hume points out that a statement can be true based on experience, or because it

is a logical truth, but NO OTHER WAY!


But those 4 common sense beliefs could not be justified

either way.They are not based on

experience (not a posteriori)and they are not logical truths (not analytic).


Kant agrees with Hume’s analysis of the problem, but

has a more ingenious solution than Hume. For Hume, these 4 beliefs are simply habits of mind.


Kant’s solution requires a radical revision in our

understanding of the way knowledge of the world

comes about.


Kant calls his solution:

THE COPERNICAN REVOLUTION IN PHILOSOPHY

THE COPERNICAN THE COPERNICAN REVOLUTION IN PHILOSOPHYREVOLUTION IN PHILOSOPHY

The original Copernican Revolution was in Astronomy.

Copernicus theorized that the Earth revolves around the sun and not the other way around

as most thought.


Just as Copernicus replaced a passive Earth

with an Earth actively involved in the motion of the

heavens…


Kant would replace the notion of a passive mind

with that of an active mind that actively constructs knowledge of the world.


Kant saw an analogy between what Copernicus did to astronomy and what

he was about to do to philosophy.


What is Kant’s solution? What does he mean by an

active mind?

Let’s look at

Kant’s Active Mind Theory of Knowledge.

Kant’s Active Mind Theory Kant’s Active Mind Theory of Knowledgeof Knowledge

Kant realized that Hume’s skeptical argument

(sometimes called Hume’s fork) demonstrated that

neither the rationalists nor the empiricists could

account for our knowledge.


Yet Kant insisted that we do know that:

1. There is a physical world.

2. I exist.


4. The causal laws will not change.


To explain how we can know these things (despite Hume’s

argument) requires that Kant rethink the whole

picture of how knowledge is acquired.


Both the rationalists and the empiricists must have

made some unrecognized mistaken

assumption. Kant thought he knew what that assumption was.


We might call that mistaken and unrecognized

assumption:

The Passive Mind Theory of Knowledge

The Passive Mind Theory of The Passive Mind Theory of KnowledgeKnowledge

Both the rationalist and the empiricist shared the basic picture of how

knowledge is acquired.


We can picture it using a cartoon.


We need a world “out there” to be known:


A person to do the knowing:


And the knowledge itself.


This IS the passive mind theory of knowledge.


The only difference between the rationalists and the empiricists is about what connects our knowledge

to reality.


For rationalists, our REASON

is able to directly grasp at the nature of reality.


For empiricists, our senses

are able to directly grasp at the nature of reality.

Notice that KNOWLEDGE OF

REALITY

is a perfect copy of

REALITY ITSEF.


As long as our knowledge

is a perfect copy of

REALITY ITSEF…


Then our knowledge is accurate.


But …

How could we ever know that?


After all, we can NEVER compare the two!



All we ever deal with is our knowledge of reality…

Never reality itself.


Since we can NEVER compare the two, we can never know

if our knowledge is accurate.


Thus we are inevitably lead to Hume’s skepticism!


Kant realized that what is required is a complete

rejection of

The Passive Mind Theory of Knowledge.


So now we must try to picture Kant’s “Active Mind”

alternative.


First, reality itself is independent of us, so it is

forever unknowable!

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Kant calls reality itself,

NOUMENAL REALITY.

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It is the source of the content of our knowledge.

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But the mind must add structure or form to render

the content knowable.


It is the interaction of reality itself and the knowing mind

That allows the construction of our knowledge or reality.

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Kant calls reality as we know it,

PHENOMENAL REALITY.?

Overcoming Hume’s Overcoming Hume’s SkepticismSkepticism

How does the Active Mind Theory answer Hume’s

argument?

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Hume showed that many of our beliefs about reality could not

be justified.

They were neither analytic truths of reason nor a posteriori

truths of experience.


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Beliefs including:1. There is a physical world.

2. I exist.


4. The causal laws will not change.


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These beliefs are not based on reason alone (not analytic)

yet not based on experience (not a

posteriori).


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Although these beliefs are not analytic, they do come from

the mind, insists Kant.


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They are not derived from experience, they are

imposed ON experience.


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Here is where the mind plays an ACTIVE role.

The mind ACTIVELY imposes these beliefs on reality as

structures, or RULES.


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So, the belief that there is an independent physical world “out there” is not based on

there being a physical world “out there,”

But is a rule imposed on reality by the mind!


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And, the belief that there is an I (self or mind) doing the

experiencing of that world

is a rule imposed on reality by the mind!


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And, the belief that

Every event is caused



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Finally, the belief that the causal laws will not change



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All the beliefs that Hume could not justify

are rules imposed on reality by the mind!


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These beliefs are not analyticAnd they are not a posteriori.

They are informative beliefs about reality, thus are

synthetic.


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These beliefs are not analyticAnd they are not a posteriori.

They are not BASED ON experience, but are

IMPOSED ON experience,


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These beliefs are not analytic

And they are not a posteriori.

Thus they are a priori beliefs.


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Kant’s ACTIVE MIND THEORY OF KNOWLEDGE allows for

a third kind of statement:

synthetic a priori.

Hume’s ForkHume’s Fork

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Hume’s fork allowed only analytic a priori truths

that come from the mind,


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And synthetic a posteriori truths

that come from reality itself.


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But now Kant introduces a third kind of truth

The synthetic a priori truths that reflect structures the mind imposes on reality.

Remember that Hume's fork allowed for only two

kinds of statements:

MATTERS OF FACT and

RELATIONS OF IDEAS.



MATTERS OF FACT

Contingent

Synthetic

A Posteriori

RELATIONS OF IDEAS

Necessary

Analytic

A Priori

Kant has now added a third prong to Hume’s Fork.


MATTERS OF FACT

Contingent

Synthetic

A Posteriori

RELATIONS OF IDEAS

Necessary

Analytic

A Priori


MATTERS OF FACT

Contingent

Synthetic

A Posteriori

RELATIONS OF IDEAS

Necessary

Analytic

A Priori

MIND IMPOSED RULES

Synthetic, A Priori Truths

RELATIONS OF IDEAS

Necessary

Analytic

A Priori

Kant’s ForkKant’s Fork

MATTERS OF FACT

Contingent

Synthetic

A Posteriori

MIND IMPOSED RULES

Synthetic, A Priori Truths

Is Kant right? Are some truths

really synthetic (informative) yet a priori (independent of

experience)?

SYNTHETIC SYNTHETIC A PRIORIA PRIORI

According to Kant, the mind not

only imposes rules (structures) to make

knowledge possible, it must also impose rules to make

experience possible!


The rules the mind imposes to

make experience possible are:

SPACE & TIME ! ! !


If Kant is correct, space and time are not “out there” independent of us.

Space and time are structures the mind necessarily imposes

on reality to render it “experiencible!”


Our common sense view of space is based on the passive

mind theory of knowledge.

We believe space is “out there” independent of us, and really

is exactly as we experience it.

SPACESPACE

Out there is space itself.

In the mind is the experience of space.

SPACESPACE

SPACESPACE

Notice that space as experienced (phenomenal space)

Is a perfect copy of reality itself (noumenal reality)

SPACESPACE

But Kant saw that Hume had shown this could not be right.

We cannot know the nature of space independent of us.

SPACESPACE

SPACESPACE

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Instead, noumenal reality is unknowable.

SPACESPACE

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But we see reality as being extended in 3 dimensions of space.

SPACESPACE

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Isn’t that because reality itself DOES extend in 3 dimensions of space? Kant says, “No!”

SPACESPACE

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If our knowledge of the 3 dimensional nature of reality came to us from reality by means of experience…

SPACESPACE

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Then our knowledge of space would be contingent, a posteriori, and synthetic.

SPACESPACE

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That would mean that we would have to allow that, even though every object we have come across so far has been spatial, one day we might find a non-spatial object.

SPACESPACE

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Can you imagine discovering a physical object, but one that did not exist in space?

SPACESPACE

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Of course not! To find an object is to find it SOMEWHERE!

SPACESPACE

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A non-spatial object makes no sense.

That shows, says Kant, that space is not experienced the way objects are.

SPACESPACE

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Space is a precondition FOR the experience of objects.

SPACESPACE

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Objects are necessarily spatial. Yet experience only gives contingent truth.

SPACESPACE

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So our knowledge of space reflects RULES our minds necessarily impose ON reality!

TIMETIME

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What about the nature of time?

TIMETIME

We tend to think about time using the passive mind theory of knowledge.

TIMETIME

Time, we think, exists independent of us.

TIMETIME

And we know about it by means of our experience of it.

TIMETIME

But Kant recognizes that Hume has shown us that if that were so:

TIMETIME

Our knowledge of time would be contingent, a posteriori, and

synthetic.

TIMETIME

Then we would have to say that, although all of the events we have experienced so far have

happened at some time,

TIMETIME

We might experience an event that occurs, but does not occur at

any time!

TIMETIME

But we cannot conceive of an event that occurs, but does not

occur at some time.

TIMETIME

So time is a precondition of experience, not derived from it.

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TIMETIME

Time, like space, is a MIND-IMPOSED RULE!

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Kant has demonstrated that space and time are really just

mind-imposed rules.

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Thus the truths about space and time are synthetic a priori truths.

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Consider the following truth about space:

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The shortest distance between any two points is a straight line.

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What kind of a truth is that?

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It is not an analytic truth, because the concept of “shortest” is not part of the meaning of “straight.”

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It is not an a posteriori truth, because it is not based on

experience.

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This belief, too, would not fit on Hume’s Fork. But with Kant’s

idea of an Active Mind,

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We get a new kind of truth…The SYNTHETIC A PRIORI.

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Trying to understand Kant’s active mind theory is not easy.

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Perhaps an analogy would help. Instead of knowledge of reality,

lets consider knowledge of…the average grade

on quiz 2.

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To know the average grade on quiz 2, I need:

all of the individual grades.

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That is the content (raw data). That is like what reality itself

provides.

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But the individual grades alone are not enough.

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That is the problem with the empiricist view. It wants reality to provide knowledge, but it only provides the content (raw

data).


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To get the average grade, I need to impose structure

(rules) on that content.


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The rule is: add together all the grades, then divide the total by

the number of grades.


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But without content, the rule is empty. That is the problem

with rationalism.


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They want the mind to furnish knowledge, but on its own it just

provides rules.


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That is like trying to find the average grade on quiz 2 by

thinking hard about the rule.


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But without the individuals grades, it won’t work.


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Instead, I need both:The individual grades (content)

and the rule (structure).


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And these rules will be SYNTHETIC, yet A PRIORI.


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Examples of synthetic a priori truths:1.The shortest distance between any

two points is a straight line.2.There is an independent physical

world.3.I exist.4.Every event is caused.5.The causal laws will not change.


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So Kant’s Copernican Revolution in Philosophy overcomes Hume’s

skepticism by making synthetic a priori truths

possible.

Kant’s Copernican Kant’s Copernican RevolutionRevolution

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But notice that there is a price to be paid.


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Phenomenal reality is such that we can rely on our 4 common sense beliefs.


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After all, our minds necessarily impose those rules on it.


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But noumenal reality (reality itself) remains forever unknowable!


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Kant has left the concept on an unknowable noumenal reality as a

challenge to all later philosophers.


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Kant’s philosophy has had an enormous influence on all later

philosophy. But Kant might not have liked all of these developments.


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For example, Kant was sure that all minds would necessarily impose the

same rules on reality (space / time / world /

self / causality / induction).


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But some later philosophers think different minds might impose different

rules.


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That leads to a form of relativism Kant would have denied.


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But it is an interesting hypothesis. When a scientist and an artist look at a

flower, do they see the same thing?


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Could a person’s reality depend on the language she speaks? Some think

so.


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But Kant was a strict universalist.All mind impose the same rules.


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As for the challenge of NOUMENAL REALITY, that will have to wait until

the study of Hegel.

T H E E N DT H E E N D

immanual kant

Documents

overcoming

kants copernican

passive mind

knowledgekant

minds necessarily

independent

fact contingent

humes fork