Kant’s Moral Philosophy

By Michael Gakuran | | Philosophy | Leave a comment |

immanuel_kant_painted_portraitKant is known for his work the ‘The Groundwork of the Metaphysics of Morals’ (or just the ‘Groundwork’) and his Categorical Imperative (CI). He sets out by analysing our general ideas and presuppositions of morality with the aim of showing that the foundations of morality are based on autonomous reason. Moreover, he thinks that we must first analyse and understand the concepts of a ‘good will’ and ‘duty’ (etc) and their relationships to one-another to further understand ethics.

He first says that ethics is material knowledge (concerned with some object) as opposed to formal knowledge (concerned with the form of understanding or reason itself) and that the laws of ethics are determined by material knowledge. In other words, ethics has to be based on laws of freedom and not on laws of nature (facts about the world) – if ethics were just based on facts about the world, we wouldn’t have control over it and hence there would be no value in acting morally.

But ethics is not empirical, it must be founded on entirely a priori principles; i.e. principles that based on reason, not on experience:

“Everyone must admit that if a law is to be morally valid, i.e., is to be valid as a ground of obligation, then it must carry with it absolute necessity … [and] that the ground of obligation here must therefore be sought not in the nature of man nor in the circumstances of the world in which he is placed, but must be sought a priori solely in the concepts of pure reason’ (G389, p894).”

For example, if we were to say that ‘One should not lie’ is a moral principle, it would have to hold true for all people and not depend on the circumstances of the situation. We likely get such ideas based on our experience at first however, and indeed, in order to effect our will we need a sharpened experience and good knowledge of the world in order to do so. But for our ideas to be moral laws, they must pass through our reason and judgement and not merely be based on our experience. In analysing ideas such as ‘one should not lie’, we are using our reason (a priori knowledge). Therefore he also thinks that ethics itself is also an a priori matter, because we must consider rationally what principles are absolute and true for everyone.

Another reason Kant feels it necessary to proceed by saying that morality must be pursued a priori is that a posteriori (experience-based) methods of investigation do not seem to tell us what we necessarily ought to do; they only seem to tell us the descriptive situation about the action we actually do perform. Kant thought that a posteriori observations could only only help us think about the conclusions of our behaviour – how satisfying our actions were and what effects they brought about. They do not help us to consider what actions are necessary and those which we are obliged to do. (For example, ‘I don’t lie because it allows people to trust me and I can have lots of friends’ would be an example of a posteriori analysis and thus Kant would not agree with it. It does not grant that I follow the principle of ‘not lying’ necessarily, because I am only doing it for some other end – to have friends or gain trust).

It is important to note that Kant is still working on ethics as a conditional until Groundwork III. He thinks that we must analyse what the supreme principle of morality is before vindicating it later. So let’s begin:

The Good Will

“There is no possibility of thinking of anything at all … which can be regarded as good without qualification, except a good will (G393, p896).” So says Kant at the start of Groundwork I. There can be other things which are good, such as courage and generosity, but unless they are grounded in a good will, they are worthless – consider the courage of a bank robber holding up a bank with a gun or the generosity of a paedophile trying lure in young children. In a similar vein, moderation of one’s passions and desires, while good, is not morally praiseworthy without a good will to back it up (consider the coolness of a villain). “The idea of a good will is supposed to be the idea of one who only makes decisions that she holds to be morally worthy, taking moral considerations in themselves to be conclusive reasons for guiding her behaviour”. (Stanford Encyclopedia of Philosophy)

Furthermore, a good will is only good in itself and not because of its fitness to produce some proposed end. It “is good only through its willing, i.e., it is good in itself (G393, p896)” and, although other gifts of talent and fortune (including happiness) are valuable, they will lack value if no sustained by a person with a good will. To elaborate more, consider Snow White and the evil stepmother. Say Snow White is a person with a pure and good will, but through the actions of her wicked sisters and stepmother, she is never allowed to actualise her good will and perform the moral deeds she desires to. Even then, according to Kant, the good will would “like a jewel, still shine by its own light as something which has full value in itself (G393, p897)”. Again, this is showing Kant’s valuing the intrinsic worth and necessity of something (the deontology) over considering its ends (consequentialism). It is helpful to note that this idea of possessing a good will is similar to Aristotle’s claim that we need to build a beautiful character by cultivating the virtues within ourselves.

Kant says that reason’s “true function must be to produce a will which is not merely good as a means to produce some further end, but is good in itself…While such a will may not indeed be the sole and complete good, it must, nevertheless, be the highest good and the condition of all the rest, even of the desire for happiness (G393, p897-8)”. As further support for needing reason to produce the good will at the crux of our being, we might consider what would happen if our purpose in life was mere happiness. Kant says that if it were so, instinct alone would drive us to be happy and fulfilled in a way much better than reason could. But we see reason as meddling with the purpose of nature; it tries in vain to find out what would make us most happy and think of a plan for attaining it. Therefore, reason’s function in us cannot just be to enable us to attain a happy and simple life. Kant supposes its function is to develop the good will, to understand morality and lead us to act from duty to fulfil our moral obligations. (This is similar to what Nagel says about reason allowing us to transcend our basic metabolic functions and act of living and our reason for thinking contemplation is a human being’s most prized goal).

Three propositions

Kant proposes 3 things:

(1) An action must be performed from duty in order to have moral worth.

Kant goes on to say that duty brings about the best in a good will. We must act from duty and not according to duty. This means that we are doing the right action because it is the right action (and abstaining from doing wrong actions because they are wrong). If we were only acting according to duty we could do actions that, although they follow the same path as morally worthy actions, are not actually morally worthy in themselves.

To elaborate on this, consider people who act out of self-interest or people who are benevolent and good-natured towards other people. Kant would say that their actions do not have moral worth. The self-interested person acts in accordance with duty, but for himself and is clearly not a good basis for a moral law. The ‘friend of mankind’, while his actions are also in accordance with duty, are not from duty. Suppose one day that he becomes depressed and his mind clouded with sorrow and he no longer feels the desire to be benevolent and kind to people. He actions would stop and the moral obligation to do certain things would go unfulfilled. This is why Kant says it is necessary to act from duty, because our feelings, desires and passions are transient and not a solid basis on which to form a moral law. But if the ‘friend of mankind’, while remaining truly good-natured and benevolent, did he actions because he thought it his duty to do so, then his actions have moral worth, for he is not basing his decisions on such changeable things as feelings. It is also useful to consider apathetic people, who have no innate emotional responses to situations. If we follow Hume’s idea that passions are the basis for morality, these people who do not have the desires to do things, but nevertheless do them out of duty, would not have moral worth. Under Kant’s philosophy, they would because they act from duty.

It seems, however, that our desires conflict with what Kant is defining as a good will and need to act from duty. We feel constrained when we are told we must follow a moral law and it goes against our desires and passions in some cases. Kant says that this is what is essential to acting out of duty. If we consider a holy being, such a being would not have the desires we do and would be motivated by thoughts independent or morality. It is because we have these desires that could cause us to act without regard for morality that we have the need for a good will and a necessity to act from duty. We need to keep them in check to maintain order.

(2) An action done from duty has moral worth only in the maxim according to which the action is determined.

“An action done from duty has its moral worth, not in the purpose to be attained by it, but in the maxim according with which the action is determined” (G399, p900).

Continuing from the first proposition, Kant makes it clear that any action must be done for it’s own sake and not for the sake of any other end. The moral worth of some action is to be found in the maxim itself rather than the effects it produces. This is the distinction between deontology and consequentialism, as consequentialists would say that the moral worth of an action is to be found in the results it brings about. If we Kant didn’t make this distinction, the difference between ‘acting from duty’ and ‘acting according to duty’ would hold no weight. By looking only at the ends of our actions we would not be able to distinguish between people who act because they reason it is their duty to do so and people who act because they desire some other end – we could all act for self-interested or even benevolent reasons because we desire some outcome. Kant says that such actions cannot have true moral worth.

(3) “Duty is the necessity of an action done out of respect for the law” (G400, p900).

Further clarifying the need for actions to be done out of adherence to the law, Kant says that “only the law itself can be an object of respect and hence can be a command” (G400, p900). This is as noted, that if I think about the effects of my actions, I am showing that I am considering other causes reasons in my analysis of a particular situation. Therefore my actions will become tainted and I will not have acted purely from duty. As such, I have to deprive “the will of every impulse that might arise for it from obeying any particular law, [such that] there is nothing left to serve the will as a principle except the universal conformity of its actions to law as such” (G402, p901). Particular laws are decided according to the ends that they realise, but by doing this we are violating Kant’s idea of adhering strictly to duty and fail to sustain the vital distinction between acting from duty and acting merely according to duty.

The above three propositions lead us to the:

Formula of the Universal Law

“I should never act except in such a way that I can also will that my maxim should become a universal law”. (G402, p901)

This is what is known as the Categorical Imperative. It rest on pure reason alone and not on experience and is a command to exercise our will in a certain way.

Quite simply, whenever considering what actions to perform, we must whether or not we can make our action into a universal law that everyone would follow. Take lying for example. I can will lying as an action, but if I try to do so as a universal law, it would necessarily destroy itself. People would not trust one another and there would be no such thing as promises, so clearly it could not become a universal law in an ordered society.

But things aren’t quite so simple. Kant goes on to distinguish between hypothetical imperatives and categorical imperatives. Imperatives are ‘ought’ statements (I ought to do some action). A hypothetical imperative applies to situations only conditionally, as a means to some other end. For example, ‘if you want to get stronger, you should go to the gym’. Therefore hypothetical imperatives are not justified in themselves but only as means to other ends.Categorical imperatives, by contrast, are unconditional and ends in themselves. They are not dependent on anything else for their justification.

Wikipedia offers a very good explanation of hypothetical imperatives, so I will include it as is: “Kant divides hypothetical imperatives into two subcategories: the rules of skill and the councils of prudence. The rules of skill are conditional and are specific to each and every person to which the skill is mandated by. The councils of prudence (or rules of prudence) are attained a priori (unlike the rules of skill which are attained via experience, or a posteriori) and have universal goals such as happiness. Thus, almost any moral “rule” about how to act is hypothetical, because it assumes that your goal is to be moral, or to be happy, or to please God, etc. The only non-hypothetical imperatives are ones which tell you to do something no matter who you are or what you want, because the thing is good in itself.”

So, to be categorical, an imperative must be good in itself and necessary to a will led by reason. But even categorical imperatives (such as ‘one must not lie’) have ends, or reasons for following them, despite being willed for their own sake and not for other ends. But what ‘end’ is this? What is the reason ‘one must not lie’? We might speak of a special, ‘The End’ – the ultimate aim of categorical imperatives leading to The Categorical Imperative.

Formula of Humanity

We have our will guiding us, led by reason. But what makes our good will objective? Why think that we can determine The Categorical Imperative by following our will and thinking a priori? There must be an end to which the will aims to justify itself. We might think of it like this:

Firstly, we are led by reason, and do not base our judgements on experience. Secondly, if we are aiming towards such an end, it must be equally valid for all human beings. Thirdly, this end must be objective (not dependent on our contingent inclinations and fourthly, it must be an end of absolute worth; worthy of being an end in itself and capable of grounding laws. Kant concludes that the end we are searching for is us, human beings, or more accurately, autonomous human beings. Human beings manifest rational nature itself: “I say that man, and in general every rational being, exists as an end in himself and not merely as a means to be arbitrarily used by this or that will” (G437, p915).

This is our freedom, our free will. To deny someone the freedom to make their own rational decisions is to treat them as a mere means to an end and undermines reason and ultimately Kant says, The Categorical Imperative. Of course, we use people as a means to an end everyday, such as taking a taxi or ordering food at a restaurant. The important thing is to not use people as a mere means to an end; to take away their own autonomy. The autonomous will is the source of moral action and decision-making, so we must always treat other people as ends in themselves. To not do so, for example by killing or maiming another person or enslaving them, is to harm their rational nature and thereby treat it as a means. In other words, we would take undermine the ‘categorical’ part of things; we would violate the will and reason on which The Categorical Imperative is based, and thus violate The Categorical Imperative. (Note this also rules out suicide because you would be violating your own rationality and will). This is known as the Formula of Humanity:

“Act in such a way that you treat humanity, whether in your own person or in the person of any other, always at the same time as an end and never merely as a means to an end” (G429, p915).

Formula of the Kingdom of Ends

As the second formulation stated, we need an autonomous will and must allow others this privilege too. But in order to universalise this law (the Formula of Humanity), we must think of the laws as binding us to others or else they would not be laws about how to conduct ourselves in society at all. Therefore Kant gives us the hypothetical notion of a ‘Kingdom of Ends’ of which all people are members:

“All maxims proceeding from [an agent’s] own legislation ought to harmonize with a possible kingdom of ends as a kingdom of nature” (G436, p919).

We ought to act only on laws which would harmonise with other people in a possible kingdom of ends. We ought to act only by maxims which would harmonize with a possible kingdom of ends. By ‘Kingdom’, Kant means: “a systematic union of different rational beings through common laws” (G422, p917). So we must not act on maxims which will create incoherent, unstable or undesirable states of affairs and only universalise those which promote harmony among people.

Applying The Categorical Imperative

Kant tries to illustrate how the Categorical Imperative would work with regards to four different situations:

(1) a suicidal person
(2) a deceitful person intending to borrow money and not repay it
(3) a person planning to neglect their talents in order to pursue pleasure
(4) a person avoiding harming others but withholding help and assistance from them

(1) and (2) are said to generate contradictions in conception and (3) and (4) are said to generate contradictions in the will when we try to universalise them. Contradictions in conception are often ‘but not exclusively) thought of as logical contradictions; i.e., there is already an error in the conception of such a possible maxim. In the suicide example, it would probably lie in the taking of one’s own life and undermining reason and the will. In the example of the person not intending to return money, it is because they are lying from the outset when they borrow the money. Contradictions in the will seem to be rules we can universalise, but fail to be acceptable to rational agents. It does not seem to merely be a logical contradiction with them as they seem to violate ‘wide duties’ that affect our general ability to pursue our ends. Such a contradiction might be labelled a ‘Practical Contradiction’ as, when universalised, such maxims would not be practical to the living of a fulfilled life.

There is much more to this debate however, including other proposed contradictions like the ‘Teleological Contradiction’. For more information, see this site: University of Victoria – Philosophy

Another complaint against the Categorical Imperative is the Triviality Charge. Some people hold that we can create universalised maxims for just about anything if we are specific enough. For example, if we say ‘I, Charlie Brown, born on 17th June 1767 can do whatever I want all the time’ or something to that effect. This is known as the problem of false positives because it passes the universalisability test (it is so specific) but it is still morally wrong. Another problem of false negatives can be illustrated by something like ‘I will go to the park on Sunday because it is quiet’. This fails the universalisability test (if everybody went to the park, it would not be quiet), but even though it fails the universalisability test, it is not a morally wrong action.

What can be said about such problems? We might say that the Categorical Imperative is not an algorithm. It cannot be effectively applied without a person’s sensitivity to something like ‘rules of moral salience’ or common sense. In the case of false negatives, we might say that the action is not deep enough to universalise and thus it lacks moral content. In the case of false positives, we might respond by saying that it is not an actual maxim because the detail involved doesn’t have anything to do with the actual situation. I.e. the person being Charlie Brown and born on a certain date does not have anything to do with the real matter at hand, which is the contradictory and non-universalisable maxim of doing anything one wants.

Another charge against the Categorical Imperative is Hegel’s famous ‘Empty Formalism Charge‘. Hegel accuses Kant of relying on ‘social institutions’. For example, Kant would say that we cannot universalise the maxim ‘always steal’ because it would lead to to the breakdown of trust and erosion of society. But Hegel says that if we didn’t have the notion of private property as an institution, we would not object to stealing in society. Similarly, universalising ‘give money to the poor’, would cause us to become poor ourselves and is thus not universalisable, but Kant seems to hold that we would want to universalise such as action. We might respond to this by saying the maxim in question can be re-formulated to something like ‘give money to those who need it’ and can be consistently held in a world where no-one requires help. With the stealing example too, it might be re-formulated to say something like ‘do not claim ownership of items which are viewed as property or in a way which would cause grief to other people’ to avoid the problems in societies where there is no notion of private property.

Some further problems for the Categorical Imperative might be as follows: Cases of the Runaway trolley – a trolley heads towards 10 people and will kill them, but you can divert it, but thereby killing one person – or Rescue – on a sinking boat, you can only save one person – do you save a family member, a doctor with the cure for cancer or a pregnant woman? Or what about organ donation – is this treating people as a means to an end (etc)?


Briefly, I will mention some of the things Kant talks about in Groundwork III:

Kant says that Freedom must be presupposed (this is what Kant calls a negative characterisation of freedom). For example, I must decide to act on my desire to do something; it won’t just happen. This is the freedom to make choices. If we do not consider that we are free, we may lapse into apathy thinking are lives are controlled or fated anyway.

Argument from Spontaneity

The positive characterisation of freedom is that a will must act for reasons, or on a principle or maxim. If it does not do because of some maxim or law, it fundamentally contradicts the idea of a will. We must find a principle for the will to act on – this is known as the ‘spontaneity of the will‘ because it must choose a law for itself. It must necessarily eliminate all possibilities except the Categorical Imperative. Other principles, such as self-love, fail because they compromise the will’s spontaneity and take things for granted (i.e. freedom). The will must be autonomous because it chooses the law to itself.

But how does the argument from spontaneity prove that the will has freedom? Just thinking that morality itself is imponderable if we aren’t free doesn’t solve the metaphysical standpoint of freedom itself.

Transcendental Idealism

Kant thinks that the phenomenal world (the world of sense) is causally determined and so cannot be the basis for genuine human freedom. He thinks that the phenomenal world that we interact with and affects us only shows us representations of objects and products of our own mental organisation. That is, we see them from the standpoint of human beings. What the objects are in themselves in the intelligible (the noumenal) world is forever unknown to us. This is known as transcendental idealism: that there is another world behind the world of appearances that we interact with. We have to see the noumenal world in order to understand the necessity of laws of nature, but we cannot do this directly. We can only conclude that the things we see in the phenomenal world exemplify laws of nature in the noumenal world.

In other words, we are necessarily ignorant of the true laws of nature, but, through reason, we can have a principled reason for knowing of the noumenal world and things in themselves. The fact that we can never know facts about the noumenal world and of objects in themselves is grounding enough for us to say that we must take it for granted that we have freedom. We can never have true theoretical knowledge of freedom, but, living in the phenomenal world where we need practical freedom in order to live our lives properly and conduct ourselves in moral situations, we must postulate that we have actual freedom.

Problems for Kant

Some more problems for Kant are briefed below:

Kant says that it is reason and not passion, that is both our motive for doing moral actions and the source of our moral obligations. Hume, in direct contrast, says that it is passion that is the source and motive of our moral requirements. But Kant is arguing that common sense dictates that our moral ideas cannot be based on our passions and desires alone. We are morally bound to perform certain actions regardless of whether or not we have the relevant desire to do some action. Having the desire to do it is good, but for an action to be morally praiseworthy, it must be done on the basis of reason and duty alone. This is what distinguishes Kant from Hume’s ideas of morality, as well as Aristotle’s focus on virtues and Mill’s focus on the consequences of one’s actions. But does Hume not have a point in saying that we are always motivated to action by a passion or desire? Doesn’t our duty spring out of a motivation to develop such an objective system such as the Formula of the Universal Law at first? Or is the reason we do so entirely based on reason?

Kant seems to show a distrust towards sympathy and emotions. Does he assume that human sentiments are intrinsically selfish (psychological egoism)? Perhaps not, as he describes amiable people as ‘friends of mankind’. Kant also seems to think the emotions are unreliable, but perhaps some emotions can be stable and enduring? Why can we assume that the motive of duty is reliable and constant?

Kant could be called cold for dismissing the importance sentiment holds in our day-to-day actions. He seems too focussed on the creating of rules and sacrifices human warmth which we highly value in society. An agent only acting out of duty and not because they possess a kind heart seems somewhat scary and disagreeable. It seems that we want emotional responses and passions, such as love and friendship to feature in our moral decision making. But Kant’s defenders have argued that what is crucial is that the motivational structure of the person to consider duty over other interests. It is not to say that we can disregard emotional responses; only that, when responding to situations, we need to put acting from duty as our highest priority over more transient emotions, but having the correct emotional warmth is preferable. Perhaps in developing a ‘good will’ to start with such emotional warmth is taken as a given when responding to situations.


Sources: Lecture handouts written by my lecturer Dr. Gerald Lang, The Stanford Encyclopedia of Philosophy and ‘Classics of Moral and Political Philosophy’ (2005) by Michael Morgan

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