Europeans polled who "believe in a god", according to Eurobarometer
North Americans polled about religious identity
Positions on the existence of God can be divided along numerous axes, producing a variety of orthogonal classifications. Theism and atheism are positions of belief (or lack of it), while gnosticism and agnosticism are positions of knowledge (or the lack of it). Ignosticism concerns belief regarding God's conceptual coherence. Apatheism concerns belief regarding the practical importance of whether God exists.
For the purposes of discussion, Richard Dawkins described seven "milestones" on his spectrum of theistic probability:
- Strong theist. 100% probability of God. In the words of C.G. Jung: "I do not believe, I know."
- De facto theist. Very high probability but short of 100%. "I don't know for certain, but I strongly believe in God and live my life on the assumption that he is there."
- Leaning towards theism. Higher than 50% but not very high. "I am very uncertain, but I am inclined to believe in God."
- Completely impartial. Exactly 50%. "God's existence and non-existence are exactly equiprobable."
- Leaning towards atheism. Lower than 50% but not very low. "I do not know whether God exists but I'm inclined to be skeptical."
- De facto atheist. Very low probability, but short of zero. "I don't know for certain but I think God is very improbable, and I live my life on the assumption that he is not there."
- Strong atheist. "I know there is no God, with the same conviction as Jung knows there is one."
The Catholic Church, following the teachings of Paul the Apostle, Thomas Aquinas, and the First Vatican Council, affirms that God's existence "can be known with certainty from the created world by the natural light of human reason".
Traditional religious definition of God: personal, omnipotent, benevolent, transcendent
In classical theism, God is characterized as the metaphysically ultimate being (the first, timeless, absolutely simple and sovereign being, who is devoid of any anthropomorphic qualities), in distinction to other conceptions such as theistic personalism, open theism, and process theism. Classical theists do not believe that God can be completely defined. They believe it would contradict the transcendent nature of God for mere humans to define him. Robert Barron explains by analogy that it seems impossible for a two-dimensional object to conceive of three-dimensional humans.
In modern Western societies, the concepts of God typically entail a monotheistic, supreme, ultimate, and personal being, as found in the Christian, Islamic and Jewish traditions. In monotheistic religions outside the Abrahamic traditions, the existence of God is discussed in similar terms. In these traditions, God is also identified as the author (either directly or by inspiration) of certain texts, or that certain texts describe specific historical events caused by the God in question or communications from God (whether in direct speech or via dreams or omens). Some traditions also believe that God is the entity which is currently answering prayers for intervention or information or opinions.
Ibn Rushd a 12th-century Islamic scholar
Many Islamic scholars have used philosophical and rational arguments to prove the existence of God. For example, Ibn Rushd, a 12th-century Islamic scholar, philosopher, and physician, states there are only two arguments worthy of adherence, both of which are found in what he calls the "Precious Book" (The Qur'an). Rushd cites “providence” and “invention” in using the Qur'an's parables to claim the existence of God. Rushd argues that the Earth's weather patterns are conditioned to support human life; thus, if the planet is so finely-tuned to maintain life, then it suggests a fine tuner - God. The Sun and the Moon are not just random objects floating in the Milky Way, rather they serve us day and night, and the way nature works and how life is formed, humankind benefits from it. Rushd essentially comes to a conclusion that there has to be a higher being who has made everything perfectly to serve the needs of human beings.
Moses ben Maimon, widely known as Maimonides, was a Jewish scholar who tried to logically prove the existence of God. Maimonides offered proofs for the existence of God, but he did not begin with defining God first, like many others do. Rather, he used the description of the earth and the universe to prove the existence of God. He talked about the Heavenly bodies and how they are committed to eternal motion. Maimonides argued that because every physical object is finite, it can only contain a finite amount of power. If everything in the universe, which includes all the planets and the stars, is finite, then there has to be an infinite power to push forth the motion of everything in the universe. Narrowing down to an infinite being, the only thing that can explain the motion is an infinite being (meaning God) which is neither a body nor a force in the body. Maimonides believed that this argument gives us a ground to believe that God is, not an idea of what God is. He believed that God cannot be understood or be compared.
Non-personal definitions of God
In pantheism, God and the universe are considered to be the same thing. In this view, the natural sciences are essentially studying the nature of God. This definition of God creates the philosophical problem that a universe with God and one without God are the same, other than the words used to describe it.
Deism and panentheism assert that there is a God distinct from, or which extends beyond (either in time or in space or in some other way) the universe. These positions deny that God intervenes in the operation of the universe, including communicating with humans personally. The notion that God never intervenes or communicates with the universe, or may have evolved into the universe, makes it difficult, if not by definition impossible, to distinguish between a universe with God and one without.
Debate about how theism should be argued
In Christian faith, theologians and philosophers make a distinction between: (a) preambles of faith and (b) articles of faith. The preambles include alleged truths contained in revelation which are nevertheless demonstrable by reason, e.g., the immortality of the soul, the existence of God. The articles of faith, on the other hand, contain truths that cannot be proven or reached by reason alone and presuppose the truths of the preambles, e.g., the Holy Trinity, is not demonstrable and presupposes the existence of God.
The argument that the existence of God can be known to all, even prior to exposure to any divine revelation, predates Christianity. St. Paul made this argument when he said that pagans were without excuse because "since the creation of the world God's invisible nature, namely, his eternal power and deity, has been clearly perceived in the things that have been made". In this Paul alludes to the proofs for a creator, later enunciated by St. Thomas and others, but that had also been explored by the Greek philosophers.
Another apologetical school of thought, including Dutch and American Reformed thinkers (such as Abraham Kuyper, Benjamin Warfield, Herman Dooyeweerd), emerged in the late 1920s. This school was instituted by Cornelius Van Til, and came to be popularly called presuppositional apologetics (though Van Til himself felt "transcendental" would be a more accurate title). The main distinction between this approach and the more classical evidentialist approach is that the presuppositionalist denies any common ground between the believer and the non-believer, except that which the non-believer denies, namely, the assumption of the truth of the theistic worldview. In other words, presuppositionalists do not believe that the existence of God can be proven by appeal to raw, uninterpreted, or "brute" facts, which have the same (theoretical) meaning to people with fundamentally different worldviews, because they deny that such a condition is even possible. They claim that the only possible proof for the existence of God is that the very same belief is the necessary condition to the intelligibility of all other human experience and action. They attempt to prove the existence of God by means of appeal to the transcendental necessity of the belief—indirectly (by appeal to the unavowed presuppositions of the non-believer's worldview) rather than directly (by appeal to some form of common factuality). In practice this school utilizes what have come to be known as transcendental arguments. In these arguments they claim to demonstrate that all human experience and action (even the condition of unbelief, itself) is a proof for the existence of God, because God's existence is the necessary condition of their intelligibility.
Alvin Plantinga presents an argument for the existence of God using modal logic. Others have said that the logical and philosophical arguments for and against the existence of God miss the point. The word God has a meaning in human culture and history that does not correspond to the beings whose existence is supported by such arguments, assuming they are valid. The real question is not whether a "most perfect being" or an "uncaused first cause" exist. The real question is whether Jehovah, Zeus, Ra, Krishna, or any gods of any religion exist, and if so, which gods? On the other hand, many theists equate all monotheistic or henotheistic "most perfect Beings", no matter what name is assigned to them/him, as the one monotheistic God (one example would be understanding the Muslim Allah, Christian Yhwh, and Chinese Shangdi as different names for the same Being). Most of these arguments do not resolve the issue of which of these figures is more likely to exist. These arguments fail to make the distinction between immanent gods and a Transcendent God.
Somesalvation is by faith", and that faith is reliance upon the faithfulness of God. The most extreme example of this position is called fideism, which holds that faith is simply the will to believe, and argues that if God's existence were rationally demonstrable, faith in its existence would become superfluous. Søren Kierkegaard argued that objective knowledge, such as 1+1=2, is unimportant to existence. If God could rationally be proven, his existence would be unimportant to humans. It is because God cannot rationally be proven that his existence is important to us. In The Justification of Knowledge, the Calvinist theologian Robert L. Reymond argues that believers should not attempt to prove the existence of God. Since he believes all such proofs are fundamentally unsound, believers should not place their confidence in them, much less resort to them in discussions with non-believers; rather, they should accept the content of revelation by faith. Reymond's position is similar to that of his mentor Gordon Clark, which holds that all worldviews are based on certain unprovable first premises (or, axioms), and therefore are ultimately unprovable. The Christian theist therefore must simply choose to start with Christianity rather than anything else, by a "leap of faith". This position is also sometimes called presuppositional apologetics, but should not be confused with the Van Tillian variety.
Christians note that the Christian faith teaches "
The atheistic conclusion is that the arguments and evidence both indicate there is insufficient reason to believe that any gods exist, and that personal subjective religious experiences say something about the human experience rather than the nature of reality itself; therefore, one has no reason to believe that a god exists.
Positive atheism (also called "strong atheism" and "hard atheism") is a form of atheism that asserts that no deities exist. The strong atheist explicitly asserts the non-existence of gods. Strong atheists further assert that the existence of gods is logically impossible, stating that the combination of attributes which God may be asserted to have (omnipotence, omniscience, omnipresence, transcendence, omnibenevolence) are logically contradictory, incomprehensible, or absurd, and therefore the existence of such a god is a priori false. Metaphysical naturalism is a common worldview associated with strong atheism.
Negative atheism (also called "weak atheism" and "soft atheism") is any type of atheism other than positive, wherein a person does not believe in the existence of any deities, but does not explicitly assert there to be none.
Agnosticism is the view that the truth value of certain claims—especially claims about the existence of any deity, but also other religious and metaphysical claims—is unknown or unknowable. Agnosticism does not define one's belief or disbelief in gods; agnostics may still identify themselves as theists or atheists.
Strong agnosticism is the belief that it is impossible for humans to know whether or not any deities exist.
Weak agnosticism is the belief that the existence or nonexistence of deities is unknown but not necessarily unknowable.
Agnostic theism is the philosophical view that encompasses both theism and agnosticism. An agnostic theist believes in the existence of a god or God, but regards the basis of this proposition as unknown or inherently unknowable. Agnostic theists may also insist on ignorance regarding the properties of the gods they believe in.
Agnostic atheism is a philosophical position that encompasses both atheism and agnosticism. Agnostic atheists are atheistic because they do not hold a belief in the existence of any deity and agnostic because they claim that the existence of a deity is either unknowable in principle or currently unknown in fact.
The theologian Robert Flint explains:
If a man have failed to find any good reason for believing that there is a God, it is perfectly natural and rational that he should not believe that there is a God; and if so, he is an atheist, although he assume no superhuman knowledge, but merely the ordinary human power of judging of evidence. If he go farther, and, after an investigation into the nature and reach of human knowledge, ending in the conclusion that the existence of God is incapable of proof, cease to believe in it on the ground that he cannot know it to be true, he is an agnostic and also an atheist, an agnostic-atheist—an atheist because an agnostic."
An apatheist is someone who is not interested in accepting or denying any claims that gods exist or do not exist. An apatheist lives as if there are no gods and explains natural phenomena without reference to any deities. The existence of gods is not rejected, but may be designated unnecessary or useless; gods neither provide purpose to life, nor influence everyday life, according to this view.
The ignostic (or igtheist) usually concludes that the question of God's existence or nonexistence is usually not worth discussing because concepts like "God" are usually not sufficiently clearly defined. Ignosticism or igtheism is the theological position that every other theological position (including agnosticism and atheism) assumes too much about the concept of God and many other theological concepts. It can be defined as encompassing two related views about the existence of God. The view that a coherent definition of God must be presented before the question of the existence of God can be meaningfully discussed. Furthermore, if that definition is unfalsifiable, the ignostic takes the theological noncognitivist position that the question of the existence of God (per that definition) is meaningless. In this case, the concept of God is not considered meaningless; the term "God" is considered meaningless. The second view is synonymous with theological noncognitivism, and skips the step of first asking "What is meant by 'God'?" before proclaiming the original question "Does God exist?" as meaningless.
Some philosophers have seen ignosticism as a variation of agnosticism or atheism, while others have considered it to be distinct. An ignostic maintains that he cannot even say whether he is a theist or an atheist until a sufficient definition of theism is put forth.
The term "ignosticism" was coined in the 1960s by Sherwin Wine, a rabbi and a founding figure of Humanistic Judaism. The term "igtheism" was coined by the secular humanist Paul Kurtz in his 1992 book The New Skepticism.