Assumptions
Assumption one: I proceed under the assumption that existence does indeed exist and that it possesses specific properties. Aristotle's law of identity (A is A) delineates the nature of these properties. It is an axiomatic principle from which logical laws and principles are derived. The law of identity states that something cannot be something else at the same time and in the same context. A is A and cannot be non-A at the same time and in the same context as it is A. A square circle cannot exist because it cannot be both at the same time and in the same respect. This means that there cannot exist a contradiction.
Assumption two: Consciousness is the process of perceiving reality. In an epistemological context, consciousness is axiomatic, but in a metaphysical context existence is axiomatic. In a metaphysical sense, to be conscious is necessarily to be conscious of something and this presumes that existence does exist and that it possesses specific properties. The significance of this distinction will become evident when we discuss the attributes of God.
Derivation: Since contradictions cannot exist we acknowledge logic as the final court of appeal. Logic is the art of non-contradictory identification. Logic rests on the axiomatic concept of existence existing and possessing specific properties. The law of identity's corollaries are delineated in texts on formal and informal logic. We will examine the concept of God with this assumption firmly established. We will test for internal contradictions as well as external contradictions. This means that we will apply logic to the attributes themselves as well as test for contradictions with the metaphysical primacy of existence.
Further assumption: We are examining the attributes of God under the assumption that they are intended to give us a coherent grasp of God's nature, and this is possible only if the attributes themselves are comprehensible. If they are unknowable, they are useless to us. The assertions that the theist makes with regard to their theory of God must be testable and knowable, otherwise it is useless to us and possesses no cognitive content.
Definition
Defining ones terms is a necessary preclusion to analyzing it. George Smith discusses the difficulty with defining the word God: "What, then, is meant by the word "god"? This is not a simple question. There have been many historical concepts of god, from the anthropomorphic deities of the Greeks to the omnipotent god of Christianity. Some gods are all powerful, all knowing and all good, while others are not. Some gods communicate with man, while others do not. Differences such as these make it impossible to give a detailed description of god that will encompass every religion--and secure widespread agreement on the meaning of "god" is a formidable, if not impossible, task.
Much of the confusion surrounding the idea of god stems from the fact that the word "god" is among the most abused terms in the history of man, ranking with such notorious words as "freedom," "justice" and "love". ... some people conveniently attach the word "god" to any belief with a tinge of significance, such as nature, the universe, love or an ultimate goal in ones life." [Smith;Atheism the Case Against God,31]
God may be fundamentally defined as a supernatural primary consciousness who is inherently unknowable and possesses three unlimited attributes: omnipotence, omniscience and omnibenevolence. These are the primary common denominators of most concepts of God and hence will comprise our definition of god. These attributes have been extracted from the writings of George Smith, philosopher of religion, and confirmed by introductory texts in philosophy.
The scope of this argument depends on ones acceptance of this definition. Any concept of God fundamentally defined as a supernatural being and/or as a primary consciousness is refuted by the following argument, if successful. Other concepts void of these attributes must be analyzed on their own terms.
It may be good to mention naturalistic theism since it is a trend in religious philosophy to identify God with nature. This would differ from our SUPERnatural God. These theists suggest that God is not above or beyond the natural universe but that he is omnipresent and indeed is the natural universe. George Smith has this to say of such a notion: "If one declared a belief in god, while stipulating that the term "god" was used as a synonym for the continent of North America, one's assertion would understandably be ignored or rejected as irrational. To expand this concept of god to include Europe, Asia, the planet Earth, our solar system--or the entire universe--is equally absurd." [Smith; Atheism the Case Against God,33] The theist thus obliterates the distinction between theism and atheism. The theist now makes no metaphysical assertion.
Smith makes an illustration as to show the importance of the supernatural element in the concept of God. "In another solar system, we discover an alien form of life, a form which is superior to man in all respects. These advanced creatures have an immense life span, superior strength, agility and mobility, and a superior capacity for memory and abstract thought. Does it follow, in virtue of these superior capacities, that these creatures should be designated as gods? No. Because despite the superiority of these creatures in relation to man, they are nevertheless bound by the natural laws of the universe. They are subject to the same physical and logical laws as man. If we did choose to call these beings "gods," this would mean that any creature who is superior to another creature thereby becomes a "god"--which would clearly lead to a chain of absurdities. A dog would be a god with respect to a plant. A man would be a god with respect to lower life forms. A genius would be a god in relation to a man of average intelligence, who would himself be a god when compared to a moron. ...In short, the difference between a god and natural existence must be a difference of kind, not merely of degree." [Smith; Atheism the Case Against God,37]
The supernatural being
The term supernatural has metaphysical connotations. It suggests that God is above or beyond the natural Universe. Theists rarely suggest that God exists in an actual place beyond the Universe because this is easily refuted deductively by the constituent definitions of "Universe" and "Beyond", they more often suggest that he exists without being subject to causal law and the law of identity. The term also has epistemological connotations. Epistemologically this would put God beyond human understanding. Unknowability is derived directly from the concept of the supernatural.
To exist beyond the framework of causal laws would be to exist beyond existence. This is derived directly from our first assumption. Existence by definition encompasses all that is. There is no alternative to existence ("non-existence is not a fact it is the absence of a fact." [Rand;IOE]). "To be is to be something as opposed to nothing, and to be something is to be something specific. If a God is to have any characteristics (which it must to exist), these characteristics must be specific but to assign definite attributes, to say that a being is this as opposed to that, is to limit the capacities of that being and to subject it to the uniformity imposed by those capacities. A supernatural being, if it is to differ in kind from natural existence, must exist without a limited nature-which amounts to existence without any nature at all."[Smith; Atheism the Case Against God,41] Further, deriving from our first assumption that existence possesses a specific identity which it is necessarily limited to a being who exists without a nature (identity) is to exist without existing. To exist without existing is to commit ones self to a contradiction. Therefor the concept of a supernatural being is inherently contradictory. This renders the notion invalid and void of cognitive content.
The primary Consciousness
The theist asserts that God is Metaphysically primary or axiomatic. God is said to be omnipresent and that his existence is his essence and vise versa. God's essence and existence are said to be indistinguishable because they are one in the same. "essence" refers to what a thing is; "existence" refers to that a thing is. The essence--existence dichotomy applies to every being except God because he is not made of component parts. The bible says that "I AM WHO I AM" is the only adequate answer to "what is God?". If we cannot distinguish the essence of God and his existence then we cannot distinguish him at all since man comprehends in terms of essence and existence. If we cannot apply these categories to God then we cannot comprehend him. As you will recall we derived incomprenceability from the supernatural element as well. The concept of a supernatural being and a primary consciousness both go to my thesis that the concept of God has no cognitive content. With every attribute that the theist proposes they fling themselves farther into agnosticism which is a branch of atheism.
If one is conscious, one exists. If one exists then one is subject to the law of identity. If ones consciousness is subject to the law of identity then it cannot be primary or axiomatical because it presumes that it exists and has an identity. The concept of a primary consciousness is inherently contradictory hence it cannot exist.
The inherantly Unknowable Being
God is said to be unknowable or incomprehensible. This is stated explicitly in many source as well as derived from other fundamental attributes of God. If God is Different in kind from natural existence then he is unknowable and if God is unknowable then the theist's claim to have knowledge of God is an impossibility. If God does not exist then we could have no knowledge of him and if God does exist, we again could have no knowledge of him. This unfalsifiable element makes the attribute useless and again adds no cognitive content to the concept of God.
The Omni Attributes
To exist is to be. To be is to be something. To be something is to be something specific, possessing specific properties. The omni attribute is defined as totally unlimited. This analysed with the primacy of existence demonstrates that an omniattribute cannot exist. An entity must be limited to it's identity. While the concept of a metaphysical infinite is a potentiality, epistemologically it remains an impossibility. The theist suggests that God exists without a particular nature which means that he has no nature at all, which means that he is different in kind from the natural universe which makes him incomprehensible or that it simply cannot exist. these are the only two options that can be derived from this attribute and both lead to zero cognitive content.
Omnipotence
There can be no obstacle to an omnipotent being, no difficulties that God must overcome. The necessity of employing means to accomplish an end is the consequence of limited power (or an identity, as we have seen). Therefore God cannot be said to employ means in any sense. God cannot be said to act in any manner because an action is required by a being that employs means to an end. Nor can God be said to have a purpose because purpose presumes an unattained end.
Omniscience
God is said to know the past, present and the futer infallibly and absolutely. If God or any other being knows the futer then that would mean that the futer is predetermined. without volition the concept of salvation is a farce. People would have no choice as to what they believe. The theist trys to side step this dilemma by stating that God does not impose his foreknowledge on the course of events but this does not change the fact that if one knows what will happen then it must happen. If God knows without fallibility the futer he cannot be omnipotent. If he can change the course of events he cannot have infallible knowledge of the futer, hence he cannot be omniscient.
Omnibenevlence
Obviously there is what we would call evil in the world such as murder or rape for example. If the theist claims that our concept of good and evil is invalid and Gods is the only appropriate one that is unknowable then the theists claim that God is good is equally invalid.
To be benevolent there must be a choice between good and evil. If God chooses to do evil over good and he has total power he would be immoral. If God does not know there is evil but cannot prevent it he cannot be omnipotent. If God knows there is evil and can prevent it but chooses not to he cannot be omnibenevolent.
Final Note On Omni Attributes
If God knows there is evil and can stop it but chooses not to be cannot be omnibenevolent. If God knows there is evil and cannot stop it then he cannot be omnipotent. If God does not know there is evil then he cannot be omniscient.
Summery
No attribute of God can hold up to a critical evaluation. Every attribute of the concept of God has been found to be either internally inconsistent or in contradiction to the fundamental primacy of existence. The concept here discussed adds no cognitive content to the word God. We have demonstrated that God cannot exist hence does not exist.