有神論被廣泛地定義為相信至高無上的存在或神靈。[1][2] 在一般的說法中，或與自然神論相比，該術語通常描述一神論（也稱為古典有神論）中發現的經典上帝概念，或多神教中發現的眾神，對上帝或眾神的信仰而不被拒絕。啟示是自然神論的特徵。[3][4]
無神論通常被理解為不接受或拒絕有神論最廣泛意義上的有神論，即不接受或拒絕對上帝或眾神的信仰。[5] 任何神祇的存在是未知的或不可知的聲稱是不可知論。[6][7]
三種常見的有神論為：
- 一神論：相信一位神的存在，或是相信神的唯一性。
- 多神論：信仰和崇拜許多神。
- 泛神論：將自然界與神等同起來。
基督教、伊斯蘭教、佛教、印度教、道教等等都是有神論，只是對神的解釋與理解則各有不同。
* Nielsen, Kai. Atheism. Encyclopædia Britannica. 2010 [2011-01-26]. （原始內容存檔於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 (編). 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 (編). 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 (編). Routledge Encyclopedia of Philosophy. Taylor & Francis. 1998 [2021-12-16]. ISBN 978-0-415-07310-3. （原始內容存檔於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.
