Chapter 9  Kantian Theory : The Categorical Imperative
Section 7. Reasoning with the Imperative

What is the function of reason?

Reason has a lot of functions. It has a theoretical function (science, for example) and a practical function. We are interested in the practical function -- practical in the sense that reason determines (along with emotions and desires) human behavior and choice. But the practical function can be understood to have two parts -- as a "means-ends" function, and as the moral function. Kant, as it should be clear to you by now, does not equate moral reason with the calculative reason of the utilitarians or the egoists. But he does not condemn this side of practical reason, either. It has its proper place in human life, and it is an exceedingly important place. But calculation of means and ends must be supported with a different type of reasoning -- moral reasoning.

And how does this side of human reasoning work? What is it's nature?

Human reason is principally constituted by the search for universality and necessity. This conception of reason shows Kant to be deeply and profoundly influenced by the Enlightenment, and the Enlightenment's pursuit of natural science. For Kant, this search for "natural laws" in science is the crucial aspect, the constitutive element of rationality per se. And just as the discovery of universal laws is absolutely central to natural science, so is the search for universal laws central to human morality. It is this aspect of reason which is at the heart of the demand for impartiality and justice. When a Judge make his/her decision in applying the law, we hope and trust that s/he is not driven by his or her feelings, or passions, or biases, or ambitions. No, we want the Judge to be rational -- to put aside those personal attachments which might influence his or her ability to ignore such things as the color of your skin, or the shape of your body, or the spelling of your name, or the patterns of your clothing, or the length of your hair. What matters is the law. What matters is the Judge's unbiased reason.

So it is in ethics as it is in law. The Categorical Imperative is devised by Kant to provide a formulation by which we can apply our human reason to determine the right, the rational thing to do -- that is our duty.

Kantís links

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. 

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,

Take a Quiz on formulating Maxims




Internet Encyclopedia of Philosophy's%20Ethics


The Categorical Imperative in the Twentieth Century 

Categorical Imperative

Catholic Encyclopedia

On Probabilities of Determining Maxims of Volition:
  Moral Responsibility in Applying the Categorical Imperative
by David R. Jenkins 

Glossary of Kantís terms 


Here are some links that might be of assistance:

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