Religion Within the Bounds of Mere Reason by Immanuel Kant
"Religion Within the Bounds of Mere Reason" by Immanuel Kant explores the relationship between morality and religion through the lens of his ethical philosophy, particularly the categorical imperative. Kant posits that true morality is grounded in rationality and individual freedom, suggesting that moral agents can only act ethically when guided by their conscience and the understanding of moral duty. He argues that human nature is inherently inclined towards evil, framing morality as a struggle between good and evil principles, with Jesus representing the embodiment of good.
The text is structured in four parts, addressing the nature of evil, the moral conflict humans face, the establishment of a moral community, and the critique of religious practices that rely on supernatural elements rather than ethical principles. Kant emphasizes that Christianity should be understood as a natural religion focused on morality, rather than a dogmatic belief system reliant on miracles. He ultimately advocates for a form of faith that prioritizes moral action and the pursuit of goodness over ritualistic observance, envisioning a universal ethical community where adherence to moral law signifies true devotion to God. This work encourages readers to reflect on the intersection of reason, morality, and religious belief.
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Religion Within the Bounds of Mere Reason by Immanuel Kant
First published:Die Religion innerhalb der Grenzen der blossen Vernunft, 1793 (English translation, 1838)
Edition(s) used:Religion Within the Limits of Reason Alone, translated by Theodore M. Greene and Hoyt H. Hudson. New York: Harper, 1960
Genre(s): Nonfiction
Subgenre(s): Critical analysis; philosophy; theology
Core issue(s): Church; conscience; ethics; good vs. evil; morality; reason
Overview
In Grundlegung zur Metaphysik der Sitten (1785; Fundamental Principles of the Metaphysics of Ethics, 1895; better known as Foundations of the Metaphysics of Morals, 1950), Immanuel Kant introduced the concept of the categorical imperative, the absolute moral law for his duty-based, or deontological, ethics. Kant presented the categorical imperative in five different but closely related formulations, which are generally referred to as 1, 1A, 2, 3, and 3A: “Act only according to the maxim which you could will to become universal law,” “Act only as if, by your will, the maxim of your action would become universal law,” “Act only so that you treat humanity as an end and never as a means,” “Act only as if your will, by its maxims, were the universal lawgiver,” and “Act only according to the maxims of the universal lawgiver in the potential realm of ends.”

The premise of Kant’s entire ethical philosophy, including his philosophy of religion, is the categorical imperative. It is derived from the principles of individual freedom that he developed in Kritik der reinen Vernunft (1781; Critique of Pure Reason, 1838), one of the most revolutionary books in the history of philosophy. For Kant, only a free person can be a moral agent, because moral action requires ethical decision making, and only a rational being with free will is capable of that kind of thought. Moral action consists in freely obeying one’s duty as known through conscience, without coercion or compromise and regardless of one’s personal feeling, inclination to the contrary, or expectation of certain results. Kant seeks to purge emotion from ethical reasoning, moral action, and religion. Conscience, as a gift of God, reveals the categorical imperative to each individual in each problematic ethical situation.
Because Kant reduces not all religion, but true religion, to ethics, so the philosophy of freedom in the Critique of Pure Reason and the exposition of the categorical imperative in Foundations of the Metaphysics of Morals must be presupposed throughout Kant’s philosophy of religion. Religion Within the Bounds of Mere Reason is unusually accessible among Kant’s works, yet it cannot be fully comprehended unless the reader has first assimilated the basic ideas of the other two works.
Religion Within the Bounds of Mere Reason is divided into four parts, which respectively examine, first, the radical evil inherent in human nature; second, the battle between good and evil principles for dominion over humankind; third, the victory of good over evil and the founding of an earthly Kingdom of God; and finally, the difference between true and false service to God.
Kant immediately sides in part 1 with the school of thought that regards humans as born evil rather than either good or morally neutral. He is particularly opposed to Jean-Jacques Rousseau’s optimistic view of human nature that held sway in the Romantic atmosphere of the late eighteenth century. By evil, Kant means inclined toward selfish acts inconsistent with natural moral duty. Evil stems from a Rousseauian prerational or antirational state of innocence. Reason is the remedy for evil. The advent of reason is the beginning of the triumph of goodness.
Part 2 shows Jesus as the personification of the good principle and posits the devil as the evil spirit who holds God-given legal authority over the evil principle. Conflict between good and evil may be regarded as originating from the devil tempting humans to choose him rather than Jesus as lord. God remains in control of evil, yet humans remain free to choose evil and reject God. Kant’s model of this familiar conflict is legalistic; humans are caught between God’s law and another law that is opposed to God’s but that God still allows. God is thus the ultimate lawgiver of both good and evil. Kant admits being unable to explain why God permits evil to exist. He says that natural inclinations, even though they tend toward evil, are good in themselves, insofar as they express human freedom. To use reason to rein in these inclinations is prudent, because to aspire to the moral perfection of Jesus is our duty.
Part 3 emphasizes that godly morality can be achieved only within the church and that the only truly moral people are church members. This is not to say that all church members are moral, as many are pious hypocrites. Part 4 continues this topic and savagely attacks those priests, theologians, and churchgoers who prefer to base their religion on miracles and the supernatural instead of the moral law. For Kant, any belief in any kind of supernatural element is superstition. It is belief without reason, a mockery of faith, and an insult to both the church and God.
Christian Themes
Kant defines God the Father as the author of the categorical imperative and understands Jesus Christ as its teacher on earth. Thus Jesus is the founder of the one true church, not because of his redemptive sacrifice on the cross, but because of his sermons, parables, and exemplary life as the perfect exponent of the moral law. This interpretation is expounded mainly in two sections of part 4 that consider Christianity first as a natural or pretheoretical religion, then as a learned or revealed religion.
Christianity as a Kantian natural religion is tantamount to belief in divinely sanctioned morality. It is spread and maintained by teachers rather than priests and informed by conscience rather than dogma. Its goal is unanimity of moral sentiment and universalizability of the derived maxims of moral action. Kant cites Matthew 5:20-48 to argue that the only people who please God are the morally pure. He uses Matthew 7:13-21 to show that those who act immorally cannot redeem themselves by doing good works for the church. For Kant, duty to the church is unimportant compared with duty to God.
At the more sophisticated stage of revealed religion, Christianity is characterized by theological principles interpreted through historical events such as the life of Jesus, the writing of the New Testament, and the growth of the church. Intellectuals working within the church create a learned faith that can appeal to all people. Faith is not an end in itself. Adherence to simple faith is not sufficient for salvation. The end for Kant is always morality. Kant calls even the most devout service to the church pseudoservice if it consists of obeying priests, believing dogma, or worshiping supernatural beings. True service to the church consists of following the good principle by doing one’s duty to the moral law, which Christian theology partially reveals and fully supports.
Kant also differentiates the earthly, historical, or visible church from the heavenly, universal, or invisible church. Both constitute what Kant calls an ethical commonwealth, but the former is temporal, essentially political, and therefore prone to all manner of civil conflict, while the latter is the perfectly harmonious eternal Kingdom of God. The mission of Jesus was to found the Kingdom of God on earth as an ethical commonwealth in which people would obey God’s moral law without fail, despite their evil nature.
Sources for Further Study
Daniel, David Mills. Kant’s Religion Within the Bounds of Reason Alone. London: SCM, 2006. A synopsis aimed at secondary school students and undergraduates.
Di Giovanni, George. Freedom and Religion in Kant and His Immediate Successors: The Vocation of Humankind, 1774-1800. New York: Cambridge University Press, 2005. Explains in detail how Kant’s contemporary Christian theologians misunderstood and misused his philosophy of religion.
Luft, Eric v. d. God, Evil, and Ethics: A Primer in the Philosophy of Religion. North Syracuse, N.Y.: Gegensatz, 2004. Devotes a chapter to Kant’s Reason Within the Bounds of Mere Reason and offers a new translation of selections from part 4, “On Service and Pseudo-Service Under the Control of the Good Principle, or, on Religion and Clericalism.”
Moore, A. W. Noble in Reason, Infinite in Faculty: Themes and Variations in Kant’s Moral and Religious Philosophy. London: Routledge, 2003. Reinterprets the relations among various kinds of reason, social morality, and Kant’s ethical and religious thought.
Reardon, Bernard M. G. Kant as Philosophical Theologian. Basingstoke: Macmillan, 1988. Shows how Kant can be a moralizing theist while rejecting both natural and revealed theology.