Kant's Argument from Morality for the Existence of the God

Kant's argument from morality grounds itself in the existence of morality. Morality exists if and only if at least one person exists, a person either being an agent or a being that must behave as if it were an agent; since only an end in itself can ground morality, and all other ends are merely instrumental ends for the good of a person, personhood is the only possible ground of morality. Consequently, a person should respect other persons in the same way they respect themselves, qua personhood; this it the categorical imperative, which is the fundamental theorem of morality. Since I am a person, morality exists. Given the categorical imperative, persons should be morally perfect; if obligation implies possibility, then persons can become morally perfect. However, if, as according to Kant, it is impossible to attain perfection given a finite lifespan, persons must be immortal. This requires them to have an eternally morally perfect judge to verify their perfection; this judge must therefore also be omniscient. Consequently, this judge must be omnipotent, and therefore unique.

The God

An anselmian argument establishes the existence of an omnipotent being. A lockean argument establishes that there can be at most one omnipotent being. A kantian argument establishes the moral perfection of the omnipotent being.

The anselmian argument restricts "greatness" to "power". This allows for the argument to be sound, not merely valid. The first premise is the consistency premise: the concept of an omnipotent being is logically consistent. The second premise is the possibility premise: if a concept is logically consistent, it refers to, at least, a possible object. The third premise is the actualization premise: an actualizing thing is necessarily more powerful than a merely possible thing. The conclusion is that an omnipotent being exists.

The lockean argument is as follows. If there exists at least two omnipotent beings, then either their wills are always in agreement or they come into conflict. If they are always in agreement, there is no meaningful sense in which they are different wills; what defines as agent, as an individual, is what it wills. If they come into conflict, then one of them loses and is therefore non-omnipotent. Therefore, there can be at most one omnipotent being. Thus, combined with the anselmian argument, there exists one and only one omnipotent being.

The kantian argument begins with the existence of at least one person; a person is a being which either is an agent or must behave as if it were. Persons are all bound by the categorical imperative, consequently, universal respect for personhood forms the ground of ethics. Cosquently, all persons should be morally perfect. Obligation implies possibility, therefore, moral perfection for persons is possible. However, it is impossible given a finite lifespan; therefore the soul is immortal. For non-eternally morally perfect persons, there must exist a judge which is distinct from itself which judges whether or not it achieves perfection. Therefore, this being must be omniscient. Since ignorance is evil, omniscience implies omnibenevolence.