Immanuel Kant (1724 - 1804)


The moral law

There is an objective moral law known to us by reason (not by experience or sense impressions).

For Kant, its from a priori reasoning.            

They are true if reason is true. 

This is like Descartes’ proof of god and 2 + 2 = 5.

Thus using our brains, building on “i think therefore I am” we can come up with moral laws.


These laws are no more arbitrarily invented than the laws of logic are.

These laws make no appeal to anything that is not rational.

We are conscious that the law could have been known without experience


To be a law it must have value in itself.  To be reasonable, it must accord with universal laws of reason.


To gain knowledge we must interpret.  And we need principles to interpret with.  We use the rusles of reason to do so. Therefure, the world is constructed by reasonal thoughts for us.



For example, being healthy is better, by definition, than being unhealthy. 



If not based on revealed moral maxims, then behavior is heterodox.


Many think morality comes from societies wants or happiness or God.


Also morality is prescriptive.  One cannot be aware of a moral requirement without recognizing it as a reason for acting.  It is by definition prescriptive.

I can choose freely.

But I cannot not know that it is right.

These principals are valid for every human.  Its different than pleasurable, because its not based on the sensual.



You have duties to yourself.  You  should harmonize with your rational nature.  The rational nature exists as an end in itself.


An “ought’ is an imperitive.  It is not contingent on some end.

The formula in a particular case is “if you are in situation’x’ you should do ‘y’.


Morality is not the doctrine of how we should make ourselves happy, but how we should become worthy of happiness.




Happiness is no good in and of itself (though desired)

Duty well done does something.


So if your friend is engaged to someone and gets drunk and makes out with someone else, you should tell the woman he’s engaged to.

It doesn’t matter that he’ll get mad.  It doesn’t matter that he swears he’ll never do it again.

There is a duty to seek my own perfection (moral and physical) and to make other’s perfection happen. Their happiness cannot interfere with or exploit other people.


Good will

Nothing is good in and of itself but good will.  It is not dependent on an outcome or accomplishment.

Even if you cannot help; you have no money; or its one of those situations where nothing will help;

Good will is good.

Even if the person doesn’t feel better.

Good will is good in and of itself.


Conversely, if there is no good will, there is no good deed.

If you are a nasty boy who throws rocks at passing cars and one day you are throwing rocks at cars and it hits a bank robber on the head, you are not a hero.

On the other hand, if you are trying to stop a bank robber by throwing a rock and it misses and breaks a window, you are not a bad person.


People who seek honor often appear to be doing something for the general good.  But they aren’t.

Of course the ultimate is if they do coincide.


Categorical Imperative

Act only on that maxim through which you can at the same time will that it should become a universal law.


A law is either a law that is universal, or it is not a law (it is a suggestion).

If, for ex, if there is no objective law, then we cannot judge other cultures.


What does it mean to be universal?  Not just that it applies to all rational beings; also that it requires us to treat like cases alike.  Hence applied everywhere.

            -univeral law-

Someone wants to borrow money.  He knows he can’t repay it.  What if all did that?


Getting drunk on the weekends.  What if all did that?  It’d be okay.


But what of I shall let my talents rust and devote my life to enjoyment.

He sees it as self evident that “a rational being necessarily wills that all the capacities in him should be developed, because they serve him, and are given him, for all sorts of possible purposes.

To will: to want rationally.


Only a rational being has the capacity to act in accordance with its idea of laws, that is, in accordance with principles:  in other words, it has a will.


We must will our capacities be developed for one’s own perfection and the happiness of others.  One cannot promote one’s own perfection fully without developing all one’s capacities; nor can one promote the happiness of others without their help and assistance.


A person has natural abilities but wants to party instead.  Could this be a universal law?  It could.  But he cannot will it to be universal because as a rational being he necessarily wills that his faculties be deveped and have served him.


You don’t want to help anyone.  What if noone was willing tohelp you?


Do unto others

These have a better basis than “do unto others”.  It allows your duties to yourself.

It also accounts for the relation to a criminal that wants you to drive them away from the crime.



We respect the law as it is magnificent and benevolent.

When we respect the law we respect ourselves.

We must be full of respect and treat all like ends not means.


Treat each person as a end, not a means

Don’t lie to get what you want.  The person will be unhappy.

Don’t use people.

This cannot be done if the persons goals and your goals are different.

That is because you then use yourself as a means.

But if your ends coincide...!

Not doing this is not forbidden.  And it is not required.


Kingdom of ends

Eventually, if everyone treats everyone else, including themselves, as an end, we will have a happy land.

This will be called the kingdom of ends.

In it every person will pursue their own “projects”

WA mystical body of the rational beings in it, in so far as the free will of each of them under moral laws stands in thoroughgoing systematic unity both with itself, and with the freedom of every other.


Free will

A free will and a will under moral laws are the same thing.

Freedom is the greatest good and the greatest evil.

Autonomy requires free will, but is not synonymous with it.

Free will that leads us to law by choices leads us to freedom of the will which is categorical imperative.


The actions taken out of respect for the moral law would not be possible if we were just part of a deterministic system.

To act out of respect for the law one must be influenced by the law itself.  But the law is not part of the “empirical causal order.  It is transcendental.


-phenomenal world-

The ordinary world is the world of the phenomenon (appearances).  This is the world as we can know it.

From our own eyes. This can bring no freedom.


-noumenal world-

But when we judge ourselves we are free (and in a naumenal God’s world view)

To view ourselves as part of the sensible world is to see ourselves and all our actions as causally determined.


A rational being must regard itself as intelligence (and thus not from the side of its lower powers)

First , so far as it belongs to the sensible world, it can consider itself under natural laws(heteronomy).

Secondly so far as it belongs to the intelligible world, it can consider itself under laws which are independent of nature, and not empirical, but founded only in reason.


We cannot think causally of our will.


Freechoice is noumenal.  It is lying beyond the world we can know about.  We can never explain it.

Pure reason as a purely intelligible being is not subject to the form of time..


Natural necessity of the subject applies only to those features under conditions of temporality.

We see past deeds as phenomenon. To that extent it traps us.


Pure free choice is totally out of time.  It is separate from any of the practical decisions we make in the course of our lives.

No individual action can properly be free at all , since actions take place in time.


Reason must regard itself as the author of its principles, independently of outside influences.; consequently as practical reasonm, or as the will of a rational being, it must be regarded by itself as free.  That is to say , the will of a rational being can be a will of his own unly under the idea of freedom, and from a practical point of view such a will must be ascribed to all rational beings.


Moral laws cannot be caused as they aren’t physical (only physical objects impact physical objects)


Though not seen in many people, this law cannot be shown empirically (its not in nature/empirical proof is a posteriori)

If it had a physical cause potential, we would be automata.


We cannot prove this law, but feel our freedom.  That is in relation to other posibilities.

“ought” implies can

If freedom and moral laws are illusions, they are illusions we cannot get rid of.


We can only prove that something is an a priori principle if we have somewhere to start from.  In the practical sphere the place is from pure reason or the “consciousness of freedom”.


Without the moral law we are stuck in the phenomenal & not free.WIth the moral law we can be truly free.  The usual person thinks the opposite.  They think those in the phenomenal w/out law is free.







“Every action is right if it or its maxim allows each person’s freedom of choice to coexist with the freeedom of everyone in accordance with a univerwsl law”.


Freedom is one such rational imperative.

Some actions are morally indifferent.  Theya re neither required or forbidden. Therefore, this should not be a tyranny.  If I eat a burrito or a salad for lunch is not too important.  Whether I kill someone or not IS!