Introduction to Plato’s Theory of Justice or Architectonic Theory of Justice

Plato’s theory of Justice, also known as the Architectonic theory of justice, has been an essential part of every society in every age since ancient times. The ancient Greek Philosophic tradition considers ethics to be the foundation of justice. Justice is the most critical part of a person’s morality. Plato’s theory of justice is somewhat seeking the same question of morality in his ideal theory of justice.

Why is Plato’s Theory of Justice called the Architectonic theory of justice?

Plato explains that during the construction of a building, each part is assigned to different artisans, but the architect combines it to contribute to the final outlay of the building and add to its splendor. Similarly, the three cardinal virtues – Temperance, Courage, and Wisdom – would be cultivated by Traders, Soldiers, and the Philosopher class, respectively, and Justice, the fourth virtue, would act as the architect of establishing a perfect state. Due to this inference between architecture and the organization of society, his theory is also called the Architectonic Theory of Justice.

According to Plato’s Theory of Justice, Justice does not consist in mere adherence to the laws, for it is based on the inner nature of the human spirit. It is also not the triumph of the stronger over the weaker, for it protects the weaker against the stronger.

A just state, Plato argues, is achieved with an eye to the good of the whole. In a just society, the rulers, the military, and the artisan all have to perform their prescribed duties. In such a society, the rulers are wise, the soldiers are brave, and the producers exercise self-control or temperance.

Essence of Ethics in Plato’s Theory of Justice

Ethics is the central theme of Plato’s theory of justice. It is a branch of philosophy that studies morality and seeks answers to questions of good or bad.

In other words, an individual with good moral character can create a society with good moral values and a just and rightful state at large.

The Greeks have considered ethics to be the foundation of politics and justice. According to Greek philosophy, the state comes into existence for the sake of life and continues for the sake of a good life, which makes it essential to have a “just society and a just state.”

The concept of “justice” is the central theme of Plato’s Republic; its sub-title is entitled “Concerning Justice.” For Plato, justice is a moral concept.

Barker says: “Justice is, for Plato, at once a part of human virtue and the bond that joins men together in the states. It makes man good and makes him social.”

Sabine has expressed a similar view. He says: “Justice (for Plato) is a bond that holds a society together.”

Justice resembles what is used in the Greek language, “Dikaiosyne,” a word that has a more comprehensive meaning than the word “justice.” “Dikaiosyne” means “just” and “righteousness.”

That is why Plato’s theory of justice is not regarded as legal or judicial, nor is it related to the realms of “rights” and “duties.” It does not come within the limits of law: it is, as such, related to “social ethics.”

Characteristics of Plato’s Theory of Justice

  • Justice is another name for righteousness.
  • It is more the performance of duties than the enjoyment of rights.
  • It is an individual’s contribution to society according to their abilities, capacities, and capabilities (refer to the three Cardinal Virtues).
  • It is a social morality: a person’s obligation.
  • It is the strength of the social fabric as it involves a web of the social system.

Plato Rejects Prevailing Theories of Justice

Plato rejected the traditional theory of justice, which holds that people should do what is proper or “do good to friends and harm enemies.” He believed that justice is good for all people, including both the giver and the receiver, and that it should not be used as a means of benefiting some while harming others.

Plato also rejected Thrasymachus’ radical idea that justice is always in the interest of the stronger. Instead, he argued that the ruler does not make all the laws that benefit him, and that justice is an art that is known and practiced by the ruler.

Glaucon’s Conventional Theory of Justice

Glaucon, one of Plato’s brothers, proposed a conventional theory of justice in which it is seen as artificial and the product of customs and conventions. He argued that justice is in the interest of the weaker, and that it is a means of preventing injustice through social contracts and laws.

Plato recognized the limitations of this theory, however, and saw justice as natural and universal rather than artificial and based on conventions.

What is the Essence of Plato’s Theory of Justice?

According to Plato, justice is the principle that each person should pursue a function for which they are fitted by nature, and that this should be done for the good of both the individual and society as a whole. He saw justice as a virtue that is both private (aiming at the highest good of the individual) and public (aiming at the highest good of society).

Plato believed that justice is necessary for living a good life, and that it helps to bring individuals, classes, and states together in harmony. He saw it as a bond that holds society together, and as a means of achieving specialization and excellence.

The Characteristics of the Just Society

In Plato’s philosophy, human behavior is characterized by three main sources: desire (or appetite), emotion (or spirit), and knowledge (or intellect). According to Plato, the perfect individual is one who has the ideal combination of these three qualities, and the just society is one that has individuals with the right balance of these traits in each social class.

Social Classes and Corresponding Virtues

Plato identified four virtues that correspond to each social class:

  1. Temperance is the befitting virtue of traders, whose dominant trait is desire.
  2. Courage is the befitting virtue of soldiers, whose dominant trait is spirit or emotion.
  3. Wisdom is the befitting virtue of philosophers, whose dominant trait is knowledge or intellect.
  4. Justice is the befitting virtue of the state, which creates harmony among all three social classes and is a necessary condition for human happiness.


Plato’s theory of justice is a comprehensive theory of individual and social virtue. It is a theory of moral excellence that is essential for the individual and for the state. It is a theory of individual and social responsibility that is based on the principle of specialization, the division of labor, the common good, the social contract, and equality.

Plato’s theory of justice is a moral and philosophical theory that is based on the concept of ethics and the importance of virtue. It is a theory that is relevant to all societies and all ages, as it is concerned with the foundations of justice and the good life.

Plato’s theory of justice is a valuable contribution to the understanding of justice and the good life. It is a theory that is essential for the development of a just and righteous society.

For more information on Plato’s philosophy, you may also want to read his works “The Allegory of the Cave,” “The Theory of Forms,” “The Ideal State,” and “The Republic.”

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