Natural law and positive law

• Is the law just?
• What is natural law?
• What is positive law?
• Which authors defend which theses?

Here are some tracks to understand how justice “justifies” the law: quotations from the greatest philosophers and explanations on natural and positive law will help you understand an essential concept at the foundation of our societies.

Justice makes law legitimate: natural law, positive law

How can we know what is right in law? What is the basis of law and justice? What legitimacy for the law thanks to justice?

→ The origins of law and justice

I. Natural law

A. What is natural law

1. Natural law means the law that comes from the “nature of Man”, the inalienable and sacred right of human nature, the right that exists because humans are human. It is based on perfect justice, the justice proper to human nature.

2. The notion of natural law took off during the Renaissance, by the philosopher and jurist Hugo Grotius (in 1625), then by Thomas Hobbes, John Locke, Jean-Jacques Jean-Jacques Rousseau (social contract theorists).

3. The foundations of natural law (including freedom, equality, property) are recalled in the UN in 1948.

B. Contestation of natural law

1. Pascal writes that even if there is a natural law, it is for man impossible to define it, so it loses its interest: “There are undoubtedly natural laws, but this beautiful corrupt reason has corrupted everything.” 1670

2. Karl Marx criticizes in, in 1844, the natural right: there does not exist a right which would be absolute, inherent in the human nature. The right is established only according to the society, the context and the history of this society.

3. Proudhon explains clearly in 1858 in: “Justice is human, all humans, nothing but human. It is to do it wrong to relate it, closely or remotely, directly or indirectly, to a principle superior or prior to humanity.”

II. Positive law

A. What is positive law

1. Positive law refers to the legislation, the rules, in force. Unlike natural law (which is what should be), positive law is what is, in fact (whether it is just or unjust).

2. Positive law (positive = which is established, which is based on facts), since it designates the effective legislation, varies according to the contexts, the society, the regions, and is instituted by the men.

3. Positive law theorized in this way took off with Hans Kelsen (1881–1973), although the latter contested being its representative in his work in 1962.

B. Contestation of positive law

1.” True law is right reason in accord with Nature; it is universally applicable, invariable and eternal.” The first part of this quotation from Cicero in (between 54 and51 BC) postulates the legitimacy of the law thanks to Nature, the second part opposes positive law as to its instability and versatility: here the law must be the same everywhere and at all times.

2. Baruch Spinoza reminds us that positive law cannot do without natural law: “Fish are determined, by their nature, to swim and the larger ones to eat the smaller ones; consequently, fish are masters of the water and the larger ones eat the smaller ones, by virtue of a sovereign natural right” in, 1670.

3. Leo Strauss logically proves the complementarity of positive and natural law. (Without retaining the quotation, I understand the following reasoning) “To reject natural law is to say that all law is positive, that is, that law is determined exclusively by the legislators and courts of the various countries. But it is obvious and perfectly sensible to speak of unjust laws and decisions. By making such judgments, we imply that there is a standard of right and wrong which is independent of and superior to positive law: a standard by which we are able to judge positive law, 1953.

Conclusion: natural law and positive law are so opposed that you will have noticed that the part of “Contesting natural law” is almost entirely an argument for positive law and vice versa. However, natural and positive law probably agree in a just and ideal city.