Western atheism has its roots in pre-Socratic Greek philosophy, but did not emerge as a distinct world-view until the late Enlightenment. The 5th-century BCE Greek philosopher Diagoras is known as the “first atheist,” and strongly criticized religion and mysticism. Critias viewed religion as a human invention used to frighten people into following moral order. Atomists such as Democritus attempted to explain the world in a purely materialistic way, without reference to the spiritual or mystical. Other pre-Socratic philosophers who probably had atheistic views included Prodicus, Protagoras, and Theodorus.

In philosophical scepticism, pyrrhonism is a position that refrains from making truth claims. A philosophical skeptic does not claim that truth is impossible (which would be a truth claim). The label is commonly used to describe other philosophies which appear similar to philosophical scepticism, such as “academic” scepticism, an ancient variant of Platonism that claimed knowledge of truth was impossible. Empiricism is a closely related, but not identical, position to philosophical skepticism. Empiricists see empiricism as a pragmatic compromise between philosophical scepticism and nomothetic science; philosophical scepticism is in turn sometimes referred to as “radical empiricism.”

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Axiological, or constructive, atheism rejects the existence of gods in favor of a “higher absolute,” such as humanity. This form of atheism favors humanity as the absolute source of ethics and values, and permits individuals to resolve moral problems without resorting to God. Marx, Nietzsche, Freud, and Sartre all used this argument to convey messages of liberation, full-development, and unfettered happiness.

One of the most common criticisms of atheism has been to the contrary—that denying the existence of a just God leads to moral relativism, leaving one with no moral or ethical foundation or renders life meaningless and miserable. Blaise Pascal argued this view in 1669.

A scientific (or empirical) sceptic is one who questions the reliability of certain kinds of claims by subjecting them to a systematic investigation. The scientific method details the specific process by which this investigation of reality is conducted. Considering the rigor of the scientific method, science itself may simply be thought of as an organized form of scepticism. This does not mean that the scientific sceptic is necessarily a scientist who conducts live experiments (though this may be the case), but that the sceptic generally accepts claims that are in his/her view likely to be true based on testable hypotheses and critical thinking.

Popularity: 39%

Popularity: 39%

Popularity: 39%

In practical, or pragmatic, atheism, also known as apatheism, individuals live as if there are no gods and explain natural phenomena without resorting to the divine. The existence of gods is not denied, but may be designated unnecessary or useless; gods neither provide purpose to life, nor influence everyday life, according to this view. A form of practical atheism with implications for the scientific community is methodological naturalism—the “tacit adoption or assumption of philosophical naturalism within scientific method with or without fully accepting or believing it.”

Philosophers such as Antony Flew and Michael Martin have contrasted strong (positive) atheism with weak (negative) atheism. Strong atheism is the explicit affirmation that gods do not exist. Weak atheism includes all other forms of non-theism. According to this categorization, anyone who is not a theist is either a weak or a strong atheist. The terms weak and strong are relatively recent; however, the equivalent terms negative and positive atheism have been used in the philosophical literature and (in a slightly different sense) in Catholic apologetics. Under this demarcation of atheism, most agnostics qualify as weak atheists.