The natural law tradition: Grotius, Kant, Hegel and Del Vecchio

Natural law refers to the principles of natural right and wrong and to the principle of natural justice, justice being used in the widest sense to include all forms of rightful action. It goes by several names: divine law, the law of reason, the universal law, eternal law and moral law.

Four properties are given for it, and they answer four different sub-questions:

• It is established by reason, the reason by which the world is governed — hence rational thought.
• It is eternal, because it has existed since the beginning of the world.
• It is unwritten, because it is found in no code.
• It therefore exists only in an ideal state, and differs from the law of a State.

Its practical importance is that the philosophy of natural law has inspired legislation and the use of reason in formulating a system of law.

Hugo Grotius, a Dutch jurist called the father of international law, formulated the doctrine of the social life of men, whose unique characteristic is the pursuit of peace and tranquillity with fellow men according to the measure of intelligence. That characteristic is found in natural law, because natural law is directly proportional to human intelligence.

The test of validity. Natural law is superior to all law as it is dictated by reason, and any law not in conformity with rational nature is either irrational or immoral. In the law of war and peace natural law is defined as the dictate of right reason, which points out that an act, according as it is or is not in conformity with rational nature, has in it a quality of moral base or moral necessity.

The social contract. Grotius conceived the State as an association of free men joined together for the enjoyment of rights and for their common interest, resulting from a contract by which the people transferred their sovereign power to a ruler, who acquired it as his private power. The ruler's actions in ordinary circumstances are not subject to legal control — but he is bound to observe the natural law and the law of nations. That last clause is the whole of the natural lawyer's answer to absolutism.

Grotius uses the contract for a twofold purpose: internally, to justify the absolute duty of obedience of the people to the government; internationally, to create a basis for legally binding and stable relations among States. Unlike Kant, he treats the contract as an actual fact in human history — he thought the constitution of each State had been preceded by a social contract by which each people chose the form of government it considered most suitable.

He also developed the principle pacta sunt servanda, and believed the whole universe is regulated by the law of nature.

Kant gave modern thinking a new basis which no later philosophy could ignore. In the Critique of Pure Reason he set himself the task of analysing the world as it appears to human consciousness.

• Nature follows necessity, but the human mind is free, because it can set itself purposes and exercise free will.
• Compulsion is essential to law, and a right is characterised by the power to compel.
• Man is part of reality and subject to its laws; though the sovereign comes into existence through the will of the people, man is still not free. His reason and inner consciousness make him a free moral agent, and the ultimate aim of the individual should be a life of free will — free will exercised according to reason and uncontaminated by emotion, which is the condition on which freely willing individuals can live together.
• Freedom in law means freedom from arbitrary subjection to another. Law is the complex totality of conditions in which maximum freedom is possible for all.
• The sole function of the State is to ensure observance of the law; the State is the protector and guardian of that law. The individual should not allow himself to be made a means to an end, being an end in himself.
• The social contract is an idea of reason, not a historical fact — and it is so sacred that there is an absolute duty to obey the existing legislative power. Rebellion is not justified.
• The test of a just law: a law is just only when it is at least possible that the whole population should agree to it, and only the united will of all can institute legislation.
• Kant's ideal of law bears no relation to any actual system; it is purely an ideal, to serve as a standard of comparison and not as a criterion for the validity of law. That sentence keeps Kant on the right side of the line between an ideal and a test of validity, and it is the sentence to quote against the charge that natural law makes every unjust rule void.
• His political programme: a universal world State, approached through a republican constitution based on the freedom and equality of States and a league of States to secure peace. He was doubtful of the practical possibility of a state of nations, seeing no possibility of international law without an international authority superior to the States. He favoured the separation of powers and free speech, and opposed privileges of birth, the established church and the autonomy of corporations.

Hegel developed ideal dialectism — a theoretical explanation of the universe, a way of investigating the truth of opinions by discussion and logical argument. Karl Marx later converted it into material dialectism. The basic tenet of the philosophy is neo-Kantian natural law, and the system is monistic.

The dialectic. The idea unfolds from the simple to the complex. The first stage is the thesis; hidden within it is its opposite, which when reduced to tangible categories becomes the antithesis; the two enter into synthesis, and the synthesis becomes a new thesis. This is an endless circle, and is true human history.

Reason and reality. What is reasonable is real and what is real is reasonable. The history of civilisation does not depend on the unfolding of events; there is an objective spirit as standard bearer of reason unfolding human civilisation, and the moving spirit is the idea.

Natural law in Hegel. Law is essentially made to understand the idea of freedom from its external manifestations. Hegel used the metaphor of natural law that man is free, and that passions, irrational desires and material interests must be subordinated to his rational and spiritual self; the mandate is that man should lead a life governed by reason and respect the reason of others.

Del Vecchio contrasted the ideals of law with positive law. The ideals of law should correspond to natural law, which is the higher law and provides the criteria for evaluating positive law and measuring its elements of justice; it is the basic principle guiding legal and human evolution, and respect for human autonomy belongs to it.

He takes his starting point from Kant but differs on one aspect: the State is concerned not only with the making of law but with its enforcement, and should concern itself with the social, political and economic well-being of social life.

His contribution to the revival of natural law is that the search for ideals to reform positive law lies in natural law, because natural law is part of human nature. Law is not only formal but has a special meaning and an implicit faculty of valuation; it is a phenomenon of nature, collected by history. Earlier conceptions of natural law — consent, liberty, representative democracy, conscience — have to a great extent been recognised in positive law and will further affect its evolution.

• The tenets question. State the basic tenets of the natural law school. Answer with the four properties, the test of conformity to reason, and the function of natural law as a standard for judging positive law rather than as a test of validity.
• The named-jurist question. Grotius, Kant, Hegel, Del Vecchio — one paragraph each, in the terms above.
• The connection to make. Duguit is said to have put natural law out of the door and accepted it through the window, because social solidarity itself rests on a natural law demand; and Fuller's internal morality is the twentieth-century form of the same tradition. A natural law answer that stops in the nineteenth century is only half an answer.