Kant and the Theistic Arguments

Immanuel Kant thought that arguments for the existence of God fell into one of three categories. Logically speaking, all classical arguments could be reduced to a form of the ontological argument, the cosmological argument, or the teleological argument (physico-theological argument). His rejection of the first two arguments was primarily due to his rejection of the ontological argument. He maintained that the cosmological argument depended on the ontological argument, such that a destruction of the ontological argument entailed the destruction of the cosmological argument.

Kant’s refutation of the ontological argument stemmed primarily from a single criticism. He denied that existence added anything to the essence of a thing. In other words, the concept “exist” does not contribute to one’s knowledge of what that thing is. The defenders of the ontological argument thought that God must have all positive perfections, including the perfection of existence. Kant rejected this because he thought that what a thing is may be properly understood without illicitly adding the property of existence. This meant that, even if the idea of God necessarily entailed the possession of all positive perfections, existence itself could not be listed among those positive perfections.

The Kantian Synthesis

Like many of the modern philosophers, Immanuel Kant became disillusioned with the philosophers before him. During his early years he was very sympathetic to the Leibnizian school. Eventually he was exposed to the writings of David Hume, and this helped him to see the weaknesses of rationalism and the importance of the empirical approach to philosophy. Rather than accepting the skeptical conclusions of Hume, Kant sought to save science and philosophy. He did not want to see the entire modern philosophical and scientific projects demolished.

Kant admired the certainty found in mathematics, but he also admired the scientific advances in physics (championed by Sir Isaac Newton). He realized that if he sided with the rationalists, he would have to minimize the importance of the physical sciences and hence the importance of the advancements made by recent scientists. If, on the other hand, he sided with the empiricists, he would have to give up certainty along with God and morality. Rather than siding with one school or the other, Kant created his own Copernican revolution in philosophy.