The Rejection of Pascal's Wager
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The Moral Argument

The next argument for God's existence was first brought forward by Immanuel Kant. We have seen that Kant was instrumental in demolishing the traditional philosophical arguments for God's existence. This he did in his major work The Critique of Pure Reason (1781). A few years later, Kant, came up with his own argument for God's existence in his second major work The Critique of Practical Reason (1788).

Kant's Moral Argument for God's Existence

Kant argued that there exists a universal sense of moral obligation. This sense of "ought", which Kant termed the "categorical imperative", points towards an objective moral law, which source can only be the supreme being or God. [1]

As Kant says in his Critique of Practical Reason:

It is our duty to promote the highest good; and it is not merely our privilege but a necessity connected with the duty as requisite to presuppose the possibility of this highest good. This presupposition is made only under the condition of the existence of God, and this condition of the existence of God, and this condition inseparably connects this supposition with duty. Therefore it is morally necessary to assume the existence of God. [2]

The existence of God is therefore to Kant a necessary postulate for what he sees to be an objectively valid morality. That morality is objective, Kant has no doubt:

Two things fill the mind with ever new and increasing admiration and awe, the oftener and the more steadily we reflect on them: the starry heavens above me and the moral law within me. [3]

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Critique of Kant's Argument

The modern reader will not find Kant's argument convincing. To understand how this argument could have been convincing to Kant, whom we all know was no mean intellect, we need to consider his personality and environmental background. He was reared among the puritans of the time and their moral ideas were deeply imbedded in his psyche. He was a man that was, according to Joseph McCabe:

More stoic that the stoics in reverence for the moral law. [4]

Kant's political environment was that of the autocratic lawgivers such as Louis IX and George I. Moral laws and legal laws were given by the king. Kant naturally applied the analogy to God as the divine lawgiver. Today, with the ascendency of liberal democracy, we no longer see that laws are made by a ruler but arose through consensus among the people represented by their elected representatives. Kant's analogous reasoning is no longer valid. There is nothing in moral laws that can compel us to believe that they owe their origins to a divine lawgiver. [a] [5]

There is another philosophical problem with Kant giving God the post as the final yardstick on morality. The error that God could supply a standard has been shown by many philosophers to be fallacious. The basic problem is that morality cannot be established simply by an appeal to authority. For instance, if "good" is defined in terms of God's commands, then it could follow that God could command anyone to cheat, steal and rape and it would still be called "good." Now if the believer objects to this and says that God can command only what is really good and we can know it, he is assuming that a moral yardstick exterior to God exists. And this, of course, invalidates the argument that God is the moral yardstick. [b] [6]

Perhaps the best summary of this objection is that of Bertrand Russell in his essay Human Society in Ethics and Politics:

Theologians have always taught that God's decrees are good, and that this is not a mere tautology; it follows that goodness is logically independent of God's decrees. [7]

The moral argument has no force as an argument for God's existence. It was the product of the cultural prejudices of a man who is otherwise one of the greatest philosophers of all time.

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a.Furthermore Kant's deeply felt sense of morality can now be explained, without any recourse to a God, by the science of evolutionary psychology .

b.This dilemma has been known at least since the time of the Greek philosopher Plato (c427-c348 BCE) and is given the name based on Plato's dialogue that dealt with this issue: Euthyphro's Dilemma.


1.Miller, God and Reason: p83
2.Ibid: p84
3.Ibid: p81-82
4.McCabe, The Existence of God: p89
5.Ibid: p93-94
6.Ayer, The Central Questions of Philosophy: p225-226
Ewing, Ethics: p112
7.Ayer, The Central Questions of Philosophy: p226

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