The concepts of peace and war, along with other related terms such as peaceful coexistence, tolerance, forbearance, or conflict and strife, must be counted among the most significant concepts in human life, as they pertain to various political, military, legal, philosophical, and social domains. What is evident is that throughout human history, all the great prophets, religious leaders, social reformers, philosophers, and even many rulers have declared the establishment of peace among individuals and nations as their foremost objective and emphasized its necessity. The issue of peace cannot be separated from other lofty and worthy human values such as freedom, justice, security, and transcendence. It has a profound and extensive connection with human nature, reason, perception, as well as ethics and virtue (al-Farabi, 1995: 120). Khawaja Naṣīr al-Dīn al-Ṭūsī (1201-1274) is among the earliest Islamic thinkers who presented comprehensive and thought-provoking discussions on peace and war in his works. Khawaja Naṣīr lived in an era marked by the Mongol invasions and plunder on one side and the bigotry and narrow-mindedness of the Abbasid rule on the other. Consequently, he was deeply concerned with safeguarding religion and homeland—rescuing religion from the distortions and oppression of the Abbasids and the homeland from the clutches of the Mongols. This led him to thoroughly explore the discourse of peace in his writings.
From Khawaja Naṣīr’s perspective, peace is an attainable concept, achievable both at the individual and societal levels. Inner peace and tranquility are prerequisites for social peace, as societal harmony cannot be realized unless individuals first attain peace within themselves (al-Ṭūsī, 1369: 298). In the Christian world, Immanuel Kant (1724–1804) was the first to propose the democratic peace theory in his work Perpetual Peace. The numerous and prolonged wars and conflicts in the West, along with the disputes between the Church and rationalists, significantly influenced Kant's pacifist thought. Kant believed that the only way to achieve peace was to abandon war and self-interest in both personal and social spheres. Thus, in Kant's philosophy, peace is defined in its negative sense—the absence of war (Kant, 1991: 93).
This research employs a descriptive-analytical method with a comparative approach to elucidate and analyze the foundations of Khawaja Naṣīr and Kant's perspectives on the issue of peace, explain their respective theories, and examine their proposed solutions for achieving peace. It further aims to highlight the distinctions and similarities in their philosophical approaches to conceptualizing peace.
Khawaja Naṣīr’s understanding and explanation of peace is not merely limited to the absence of war and conflict but is rooted in a complex and coherent system of religious beliefs and ethical values. From his perspective, peace is not only a social and political necessity but also a foundation for achieving individual and collective happiness and perfection. This, in turn, creates a suitable environment for human flourishing in all dimensions (al-Ṭūsī, 1369: 69). According to Khawaja, humans are both the origin and purpose of governance. On this basis, he emphasizes human freedom and the right to choose, ethical governance, political rationality, and the rule of a wise sovereign (al-Ṭūsī, 1336: 72). Khawaja believes that social stability stems from a government's ethical and human-centered approach, fostering peace and harmony in both domestic and foreign relations while avoiding tension and conflict.
Kant also believed that a peace which does not eliminate the grounds for future conflicts is not true peace at all but merely a temporary truce. This is because the concept of genuine peace runs deeper than the mere absence of temporary conflict. Throughout Kant’s works, there is a profound connection between politics, morality, and reason, and he analyzes peace based on these three principles. According to Kant, humans can bring an end to conflict and strife by applying the principles of practical reason and rationality. On the other hand, there are certain categorical imperatives in ethics that every individual can recognize through practical reason, guiding them toward peace (Mearsheimer, 1990: 54).
The issue of peace and war has long been among the most significant issues debated and reflected upon by thinkers from various religious and intellectual perspectives. Khawaja Naṣīr al-Dīn al-Ṭūsī in the Islamic world and Immanuel Kant in the Christian world have presented profound and thought-provoking discussions on this issue. In his discourse on peace, al-Ṭūsī seeks to articulate the concept of a “peaceful city,” where individuals can flourish alongside others in society and contribute to its prosperity and progress. He emphasizes the necessity of interaction among different groups and schools of thought within society to achieve peace. Al-Ṭūsī also highlights moral virtues such as empathy, cooperation, and benevolence as essential factors in strengthening social bonds and fostering peace and harmony in society. Kant, through his theory of perpetual peace, aims to provide humanity with a path toward a world free from war and violence. This theory not only stresses the importance of establishing republican governments and adhering to ethical principles but also underscores the necessity of cooperation and interaction among nations as a fundamental condition for achieving peace. Al-Ṭūsī regards peace-seeking as an innate human tendency, believing that all human faculties inherently strive for balance. In his view, peace—rooted in divine and natural principles—constitutes an essential aspect of human identity. In contrast, Kant approaches peace from a materialistic perspective, viewing it as a social necessity for states rather than an innate human desire. He adopts a liberalist stance, considering peace not as a natural inclination but as a rational mechanism to safeguard state interests and security.