This book ... is not a sympathetic examination or interpretation of religious doctrines; it is a straightforward critique, philosophically and psychologically, of the belief in a god, especially as manifested in Christianity.
... It is my purpose, however, to demonstrate that the belief in god is irrational to the point of absurdity; and that this irrationality, when manifested in specific religions such as Christianity, is extremely harmful.
ix, xi

Atheism is probably the least popular--and least understood--philosophical position in America today. It is often approached with fear and mistrust ...
Atheism is commonly considered to be a threat to the individual and society. It is "science divorced from wisdom and the fear of God," writes one philosopher, "which the world has directly to thank for the worst evils of 'modern war' ... [A.E. Taylor, 1947] In a recent critique of atheism, Vincent P. Miceli [1971] claims that 'every form of atheism, even the initially well-intentioned, constricts, shrinks, enslaves the individual atheist within and against himself and, eventually, as atheism reaches plague proportions among men, goes on to slave and murder society."
4

"Theism" is defined as the "belief in a god or gods." The term "theism" is sometimes used to designate the belief in a particular kind of god-the personal god of monotheism--but as used throughout this book, "theism" signifies the belief in any god or number of gods. The prefix "a" means "without," so the term "a-theism" literally means "without theism," or without belief in a god or gods. Atheism, therefore, is the absence of theistic belief. One who does not believe in the existence of a god or supernatural being is properly designated as an atheist.
Atheism is sometimes defined as "belief that there is no God of any kind," [Hick, 1963] or the claim that a god cannot exist. While these are categories of atheism, they do not exhaust the meaning of atheism--and they are somewhat misleading with respect to the basic nature of atheism. Atheism, in its basic form, is not a belief: it is the absence of belief. An atheist is not primarily a person who believes that a god does not exist; rather, he does not believe in the existence of a god. 7

First there is the familiar sense in which a person is an atheist if he maintains that there is no God, where this is taken to mean that "God exists" expresses a false proposition. Secondly, there is also a broader sense in which a person is an atheist if he rejects belief in God, regardless of whether his rejection is based on the view that belief in God is false.
- Paul Edwards, 1961 [Smith, 7-8]

"Atheism" is a privative term, a term of negation, indicating the opposite of theism. ...
"Theism" and "atheism" are descriptive terms: they specify the presence or absence of a belief in god. 8