Josh Dunigan |||

Philosophy Briefs -The Hart-Fuller Debate


Nazi Germany threw a real kink in the philosophy of legal theorists after the war was over. Nazi Germany had many laws, they had court cases, and they had lawyers and judges following legal theory at the time. How did the laws get passed and allow for such atrocities to occur? How could a philosophy of law explain what was right and what was wrong in these cases? There are laws passed all over the world that are seemingly unjust and unethical. When should one obey and disobey the law?

These are the kinds of questions that concerned H.L.A Hart and Lon Fuller. Hart is going to be advocating for a position known as the legal positivist theory of law, while Fuller is going to be advocating for the natural law position. The case that was being debated over was the grudge informers in Nazi Germany. There were people who used the Nazi laws to their advantage. For example, a wife reports that her husband was saying bad things about Hitler in private. Saying bad things about Hitler is considered illegal and the husband was sent to the front lines. Did she do something wrong there since she was following the law of the current state? If considered wrong now, can we punish her retroactively? Both Hart and Fuller agree that she did something wrong, but from different angles.

The worry for the legal positivist is that if you say that the laws should be tracking morality, you run the risk of two possible scenarios, the anarchist and the amoral person. If you say that the law as is and the law as it ought to be (morality) are the same, then someone can reject one or the other. The anarchist will reject legality and not follow any laws, since it is not tracking their idea of morality. The amoral person will just take the current system of law as their morals, thus destroying any sense of morality that they will adhere to and just follow the law.

The positivist (shortening here, there other types of positivist such as logical positivists) does not deny that law has an influence on morality and that morality has an influence on law. The constitution, the first thing made into law, is going to be influenced by morality. Once it is writing, however, it is the law and all law will follow from that. What the positivist is after is the following conclusion.

it could not follow from the fact that a rule violated standards of morality that it was not a rule of law; and, conversely, it could not follow from the mere fact that a rule was morally desirable that it was a rule of law.

The nice thing about this is that you ethics and legality are separate. You can have at the same time laws that allow for multiple religions, differing views on charity and obligations to people and animals, or many other ethical stances.


The positivists think that law is a closed circuit of logic. You have premises (previous court cases and laws), and anything that you want to decide can be done using deductive reasoning. Say there is a law that states that vehicles are not allowed in a park. What constitutes a vehicle? Is a plane a vehicle? A car? A skateboard? A rickshaw ? This problem in law is called the problems of the penumbra”. If deciding what a vehicle is is not able to be done through just the premises given by past law, then it is not a closed system and the judge in this case may need to lean on ethics to make the decision.

Hart handles this objection by saying that a judge does not necessarily just deduce from premises, their job in some cases it to legislate as well. If the law is vague, it is their job in some cases to bring about legislation to more accurately describe the law. The judge needs to adapt to the growing needs of society. When we are determining that Americans have a right to bare arms, when it was made society had no nuclear weapons, so the definition obviously did not include it. Now, someone cannot argue that they are buying wholesale uranium and making bombs, selling them to North Korea because it is their consitutional right”. It is up to judges to adapt laws to the needs of society when it is fit. To sum up this point :

the judges are only drawing out” of the rule what, if it is properly understood, is latent” within it.

The other objection is that the word ought” that the naturalists use can mean many things. When Stalin wanted to establish his terror based regime, to do it he ought to have a secret police. There are more kinds of oughts than oughts are are consistent with rules of morality. The law might require some sort of ought that is not a moral ought, thus again you can have an ought within law and not it be a moral ought.


For a positivist, once a legal authority is in place and is social accepted, then the laws put in place after that are what is and things follow. Laws may be adapted to fit the growing needs of society, but there is no necessary connection between law and morality.

Fuller and Natural Law

A concern Fuller has with Hart is that, the law under the Nazi regime still could have been called law. Hart does not think we have a duty to obey the law if you are under the Nazi regime, but that from a positivist perspective the laws posited by Nazis was still law. The dilemma that Hart is showing is that should one maintain their fidelity to law” or follow their morals in this case. Fuller will disagree with Hart on many of the points above.

One of Hart’s statements is that ought can be used by someone who is evil. If you combine morality and law, a judge may use it to make moral rules, but also may use it to make immoral rulings. Also, Hart thinks that the positivist theory has no defense against this problem as well. Furthermore, It seems entirely possible that the law could be done to pass immoral things. A state can invoke legal logic to make something a law that most people disagree with. A state can also make something immoral legal if there are enough people that support the outcome due to morals. Say, passing racist laws since the victim of those policies is a minority and cannot defend itself via numbers. Lastly, one of the things Hart said natural law would imply is people that become complacent and allow for law to replace morality, Fuller thinks that this is possible as well in positivism.

Fuller is dissapointed in Hart because Hart says that law is based on certain fundamental accepted rules specifying the essential lawmaking procedures”, yet Hart does not dive into what gives those accepted rules power. There are two cases here Fuller lays out. How does one go about instantiating the writtten law procedures that Hart mentions without already having laws written down? To create a constitution first, one needs to use moral reasons to create the constitution. Lastly, Fuller profoundly says that

No written constitution can be self-executing. To be effective it requires not merely the respectful deference we show for ordinary legal enactments, but that willing convergence of effort we give to moral principles in which we have an active belief.

We are not robots programmed to do things given some code. Morality is going to influence whether or not we follow the law and gives the law any governance over our actions. If morality is the thing that governs our actions, laws cannot be necessarily separate over us, since law does not govern without morality. If a law is passed that is wholesale immoral, no one will follow it. If no one will follow it, then lawmakers may as well have not passed the law. For this reason, Fuller states that law will converge to morality.

Fuller then states that the issues in law is that there is order and good order, law as it is and law as it ought to be and this corresponds to the demands of justice and/or morality. Law can be anything, American law or Nazi law, but determining what good law is takes more analysis of the demands of justice and morality.

For any law to be even plainly called order, it must satisfy a few criteria, even the most evil of law. Good law is law that does not depart from the inner morality of law”. One thing law has to do is to match reality. The Nazi laws were laws, but they would pick and choose when to follow them or how to follow them. Rules also need to be clear. If they are not clear, but are vague, then it is hard to even follow the law despite how unjust it is. Laws also need to be public. Laws are not able to be followed if people do not know about them, which was the case with the secret order of the Nazi. All of these are showing that for law to even have any sense of order, to have any sense of governance over peoples actions, they have to follow these. On top of it, the laws will have to adhere to some sense of morality otherwise people have no obligation to follow those laws.

Hart had another point about judges legislating and bringing out the latent meaning of the law. However, Fuller disagrees that its not just a matter of semantics. The problem for cases of penumbra is it is not certain if there are cases are violating the reason why the law was being passed. Fuller says that the reason for the law being made about the park was to keep the noise down in the park. If that is the case, an electric skateboard may be considered a vehicle by definition, but does not violate the reason the law was being passed for.

Synthesizing via Kant

There are a few issues being discussed by both people. One issue I have with both arguments is that they rule out coercion being the basis of justice. Hart never really gives a good way for law to start up or why people should follow the law. Morality is one reason why people could follow the law and not follow other ones. However, another issue with Fuller is that he shows why there might be a moral obligation to obey or not obey laws, but how do we enforce morality in other cases? Can you enforce charity if charity is ethical? Can you enforce people to not lie if lying is ethical? It seems hard to say that law converges to morality, and if it does, Hart may be correct in his analysis that people will either become anarchist or adopt legality as morality. There is an alternate view that can explain some of these.

Kant is most famous for his ethical writings, but his political philosophy has been getting more traction by people like Professor Varden. Kant’s ethics is about internal freedom. There are people and they are rational beings that can set ends of their own. A maxim (a subjective rule of action) is ethical or not if it passes some tests to determine if it is contradictory to his idea of the categorical imperative. However, his ethics do not entail any political justifications since ethics is internal and not internal.

Kant’s political philosophy is about freedom, not self-preservation. To be free is to not be constrained by someone else’s arbitrary choices, but only by universal law. The governments job is to preserve freedom through just uses of coercion. Hart and Fuller disagree with any coercion based definition of government, but Kant presents a case for this. Kant states that it is just to stop someone else from constraining someone else’s arbitrary choices. Kant also handles the issue of how one could start a state and why on ought to do this. In the state of nature, justice is only provisional for Kant at best. To get justice fully, one needs to start a state. The reason for this is not moral, but is rational. Once a state is started, a state is not off the hook for justice. By reason, there are private, public, and human rights that need to be satisfied. Once those are satisfied, then a state can truly be called a state, otherwise it is just barbarism. Once these rights are satisfied, only then can you think of the law as positivist. The laws before that do not have any rational reason to be considered just and to follow them. Since this post is mainly about Hart and Fuller, will not dive too deep into Kant, but wanted to show there is alternate theories and ways to go in this debate.


Hart argues that there is no necessary connection between law and morals, while Fuller goes in the opposite direction. While both are great arguments, they both seem to think that there idea is the only solution. Hart leaves out things in his argument, mainly, why people should follow the law and how law comes into being. Fuller gives a reason for following the law and how it comes into being, but it is not the only way law can come into being. There also issues on not only following the law, but mixing morality into ethics, since government cannot just ignore the problem of coercion. If the government is going to have purchase over people’s actions, not only do they need to be rational, they have to have some coercive power. Kant wants to respect people’s freedom and figure out how a government can justly do this. Kant is a mix between the two ideas, not purely positivist or purely natural law. A mix may be misleading too, since he starts from a different point and ends at a different point, and brings in new concepts.

Further Reading

Went over the Hart-Fuller debate in good faith to both. There are plenty of other people to read. I would recommend just starting with the Natural Law and Legal Positivism stanford.plato links. For Kant, I would recommend Professor Varden’s work as a nice starter.


  • Hart
  • Fuller
  • Kant - Taken classes under Professor Varden, so I mainly use her readings of Kant, which are linked above.
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