有神论被广泛地定义为相信至高无上的存在或神灵。[1][2] 在一般的说法中，或与自然神论相比，该术语通常描述一神论（也称为古典有神论）中发现的经典上帝概念，或多神教中发现的众神，对上帝或众神的信仰而不被拒绝。启示是自然神论的特征。[3][4]
无神论通常被理解为不接受或拒绝有神论最广泛意义上的有神论，即不接受或拒绝对上帝或众神的信仰。[5] 任何神祇的存在是未知的或不可知的声称是不可知论。[6][7]
三种常见的有神论为：
- 一神论：相信一位神的存在，或是相信神的唯一性。
- 多神论：信仰和崇拜许多神。
- 泛神论：将自然界与神等同起来。
基督教、伊斯兰教、佛教、印度教、道教等等都是有神论，只是对神的解释与理解则各有不同。
* Nielsen, Kai. Atheism. Encyclopædia Britannica. 2010 [2011-01-26]. （原始内容存档于2011-05-12）. Atheism, in general, the critique and denial of metaphysical beliefs in God or spiritual beings.... Instead of saying that an atheist is someone who believes that it is false or probably false that there is a God, a more adequate characterization of atheism consists in the more complex claim that to be an atheist is to be someone who rejects belief in God for the following reasons (which reason is stressed depends on how God is being conceived)...
- Edwards, Paul. Atheism. Donald M. Borchert (编). The Encyclopedia of Philosophy Vol. 1 2nd. MacMillan Reference USA (Gale): 359. 2005 [1967]. ISBN 9780028657806.
On our definition, an 'atheist' is a person who rejects belief in God, regardless of whether or not his reason for the rejection is the claim that 'God exists' expresses a false proposition. People frequently adopt an attitude of rejection toward a position for reasons other than that it is a false proposition. It is common among contemporary philosophers, and indeed it was not uncommon in earlier centuries, to reject positions on the ground that they are meaningless. Sometimes, too, a theory is rejected on such grounds as that it is sterile or redundant or capricious, and there are many other considerations which in certain contexts are generally agreed to constitute good grounds for rejecting an assertion.
(page 175 in 1967 edition)
Hepburn, Ronald W. Agnosticism. Donald M. Borchert (编). The Encyclopedia of Philosophy Vol. 1 2nd. MacMillan Reference USA (Gale): 92. 2005 [1967]. ISBN 9780028657806. In the most general use of the term, agnosticism is the view that we do not know whether there is a God or not.
(page 56 in 1967 edition) Rowe, William L. Agnosticism. Edward Craig (编). Routledge Encyclopedia of Philosophy. Taylor & Francis. 1998 [2021-12-16]. ISBN 978-0-415-07310-3. （原始内容存档于2021-12-16）. In the popular sense, an agnostic is someone who neither believes nor disbelieves in God, whereas an atheist disbelieves in God. In the strict sense, however, agnosticism is the view that human reason is incapable of providing sufficient rational grounds to justify either the belief that God exists or the belief that God does not exist. In so far as one holds that our beliefs are rational only if they are sufficiently supported by human reason, the person who accepts the philosophical position of agnosticism will hold that neither the belief that God exists nor the belief that God does not exist is rational.
