Chapter  8: ETHICS

The Categorical Imperative

(NOTE:  You must read only those linked materials that are preceded by the capitalized word READ.)   

Immanuel  Kant

The Categorical Imperative Immanueal Kant An Ethics of Duty   

For Kant the basis for a Theory of the Good lies in the intention or the will.  Those acts are morally praiseworthy that are done out of a sense of duty rather than for the consequences that are expected, particularly the consequences to self.  The only thing GOOD about the act is the WILL, the GOOD WILL.  That will is to do our DUTY.  What is our duty?  It is our duty to act in such a manner that we would want everyone else to act in a similar manner in similar circumstances towards all other people.

Kant expressed this as the Categorical Imperative. 

Act according to the maxim that you would wish all other rational people to follow, as if it were a universal law. 

For Kant the GOOD involves the Principle of Universalizability!  

Kant argues that there can be four formulations of this principle:

The Formula of the Law of Nature: "Act as if the maxim of your action were to become through your will a universal law of nature."

The Formula of the End Itself: "Act in such a way that you always treat humanity, whether in your own person or in the person of any other, never simply as a means, but always at the same time as an end."

The Formula of Autonomy: "So act that your will can regard itself at the same time as making universal law through its maxims."

The Formula of the Kingdom of Ends: "So act as if you were through your maxims a law-making member of a kingdom of ends." 

Never treat a person as a means to an end.

Persons are always ends in themselves.  We must never use or exploit anyone for whatever purpose. 

VIEW: Kant and Categorical Imperatives: Crash Course Philosophy #35

Video: Beginner's Guide to Kant's Moral Philosophy

The Categorical Imperative is NOT the Golden Rule

Kant’s Deontology is presented in his  Groundwork for the Metaphysics of Morals

Kant in his Critique of Practical Reason wanted to find a basis for ethics that would be based on reason and not on a faith in a god or in some cold calculation of utility that might permit people to be used for the benefit of the majority.  Kant thought carefully about what it is that all humans would find reasonable as a guide for human conduct.  People think it wrong to kill, lie, steal, and break promises.  Why is this so.  Kant arrives at the idea that humans think these acts wrong because they cannot will that others would do these things because it would mean the end of civilized life, perhaps even the life of the actor contemplating the right way to behave.  One can not will that people lie all the time for that would mean the end to human communications if we could not trust what was said to be true most, if not all, of the time.  Kant thought that there would be perfect and imperfect duties. 

Perfect Duty is that which we are all obliged to do all of the time. 

e.g., no killing, no physically harming others, no lies, no theft, no breaking promises 

Imperfect Duties are those which we should do as often as possible but can not be expected to do always.         e.g., be charitable, loving,

COMPLETE OVERVIEW of KANT and the ETHICS of DUTY  inREAD: wikipedia on Kant

Internet Encyclopedia of Philosophy on Kant's Ethics 

 Internet Encyclopedia of Philosophy on Kant's Metaphysics  

Philosophy Pages on Kant

The Categorical Imperative in the Twentieth Century

Catholic Encyclopedia

The Categorical Imperative is NOT the Golden Rule

With the Golden rule you are to:   Act as you would have others act towards you. 

The Golden Rule Around the World

The same essential golden rule has been taught by all the major religions (and philosophies) of the world going back approximately 3500 years.  Here are just some examples.

HINDUISM (Vedic religion from c. 13th century BC)

Do not to others what ye do not wish done to yourself...

--This is the whole Dharma, heed it well.

The Mahabarata, -Brihaspati (Anusasana Parva-Section CXIII Verse 8

ZOROASTRIANISM (c. 12th century BC)

Human nature is good only when it does not do unto another whatever is not good for its own self.

Dadistan-i-Dinik, 94:5;  

BUDDHISM (c. 6th century BC)

Hurt not others in ways that you yourself would find hurtful.

   Udanavargu, 5:18, Tibetan Dhammapada, .

JUDAISM (c. 10th? century BC)

Torah verse (Hebrew: "ואהבת לרעך כמוך"):

You shall not take vengeance or bear a grudge against your kinsfolk. Love your neighbor as yourself: I am the LORD. Leviticus 19:18

That which is hateful to you, do not do to your fellow. That is the whole Torah; the rest is the explanation; go and learn it.------Hillel in Talmud, Shabbat 31a

JAINISM (c. 6th century BC)

In happiness and suffering, in joy and grief,

regard all creatures as you would regard your own self.


CHRISTIANITY (c. 1st century AD)

Do unto others as you would have them do unto you.

Luke 6:13

So in everything, do to others what you would have them do to you.    Matthew 7:12

For all the law is fulfilled in one word, even in this; Thou shalt love thy neighbour as thyself.--Paul -Galatians 5:14

CONFUCIANISM (c. 6th century BC)

     Do not do to others what you do not want done to yourself.

Confucius, Analects, 15:23, 6:28; Mahabharara, 5:1517,

in Confucius, The Analects,

ISLAM (c. 7th century AD)

No one of you is a believer until you desire for another that which you desire for yourself.

The Sunnah (from the Hadith),

SIKHISM (c. 15th century AD)

Be not estranged from another for, in every heart, Pervades the Lord.

Sri Guru Granth Sahib, in Singh


BAHÁ'Í (c. 19th century AD)

Ascribe not to any soul that which thou wouldst not have ascribed to thee, and say not that which thou doest not. This is my command unto thee, do thou observe it.

     Bahá'u'lláh, The Hidden Words, Arabic 29

For more references and appearances of variations see wikipedia on the Golden Rule 

See also:

Why should willingness to be on the receiving end of like action make it permissible? If masochists are willing to suffer others' sadism, would that make sadism right? More generally, can acceptance of being on the receiving end of like action legitimate anything?

Kant's improvement on the golden rule, the Categorical Imperative:

Act as you would want all other people to act towards all other people.

Act according to the maxim that you would wish all other rational people to follow, as if it were a universal law.  

The difference is this.  With the Golden rule a masochist or a sadist would be justified in causing or receiving pain.  This is not what the Kantian Principle would support. 

From Don Berkich:

" Some  make the mistake of thinking that the First Formulation of the Categorical Imperative is but a badly worded version of the Biblical "Golden Rule"--Do unto others as you would have them do unto you. Nothing could be further from the truth.

The Golden Rule, as Kant well knew, is a deeply misguided ethical principle. To see this, consider the following somewhat salacious example.

The Horny Martin Example




Suppose that Martin is 20 year-old college student. Suppose further that Martin has never been out on a date. The woman of his dreams finally agrees to go out with him. So Martin gets all dressed up and takes her out to a nice dinner, after which they drive up to Lookout Point. And...


Martin does unto others as he would have done unto himself,

with disastrous consequences.

Because the same result cannot be obtained by application of the Categorical Imperative, it follows that the Golden Rule and the Categorical Imperative are not extensionally equivalent. "

The Categorical Imperative is NOT the Golden Rule


1. The theory applies only to rational agents.  It would not apply to non-humans or to humans who are not rational, e.g., humans with brain malfunctioning, illness or persistent vegetative coma.  

2. The theory cannot resolve conflicts between duties:

a.     between two perfect duties

b.     between a perfect duty and an imperfect duty  

How would a person resolve a conflict between two perfect duties such as never tell a lie and avoid harming someone?  What if telling the truth were to harm someone?

How would you resolve the conflict between the perfect duty, say to keep a promise to pick your friend up with you auto at a certain time, and an imperfect duty, say to stop on the way to pick up your friend in order to give CPR to someone, a stranger, and save that stranger’s life? 

3. A clever person could phrase the maxim to be universalized in such a manner as to permit almost anything.  By placing qualifiers on the maxim or peculiar definitions on terms a clever actor could satisfy the categorical imperative and yet be acting in a manner otherwise not consistent with it. 

What if someone were to promise to be faithful to his mate and not have sex with another woman.  Then that person engages in oral and anal forms of physical interaction leading to orgasm and yet thinks that the promise was not broken because the meaning of “sex” did not include those forms of interaction.


Glossary of Kant’s terms 

Kant links   

·         Groundwork for the Metaphysics of Morals 

 GrGroundwork for the Metaphysics of Morals 

·       Kant at

·         The Ethics of Duty  

·         What is the best way to live? Kant

·         A Critique of the Kantian Ethics  

·         Critique of Kant 

·         Kant, Immanuel: The Critique of Practical Reason  

·         Kant, Immanuel: The Critique of Pure Reason  

·         Kant, Immanuel: Fundamental Principles      

      Internet Encyclopedia of Philsoophy (IEP ) on Duties and Deontology -

        Categorical Imperative -       

German Idealism -

       Kant, Immanuel -- Metaphysics -

        On the A Priori  

        A Critique of the Kantian Ethics by Michael Huemer Spring, 1993 -

        Critique of Kant in Schopenhauer's Thesis: On the Basis of Morality Andreas Wißmiller

          Kant in History of Ethics by Darwall, -

There are other theories.  We shall move on to examine them.

Proceed to the  next section.

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