Over the years on sciforums, we have had several threads in which members have discussed what they understand to be the meanings of the terms "theist", "atheist" and "agnostic". I have started several threads on the topic myself. It seems to me that in the early 21st century, people have been working towards a consensus about the meanings of these terms. I am wondering whether we can agree on these matters here on sciforums in 2025.
Here's my latest crack at it, for discussion and possible debate.
Two independent axes
Agnosticism is often conceptualised or explained as a "middle ground" between theism and atheism. However, I assert that agnosticism is best understood as lying on a perpendicular axis to the theism-atheism axis. Thus, we have the theist/atheist distinction and another, independent, gnostic/agnostic distinction.
All four combinations are possible, such that it is quite reasonable for a person to self-identify as a gnostic atheist, an agnostic atheist, a gnostic theist or an agnostic theist.
About belief
To say that one believes a claim is to assert that one accepts that the claim is true or very likely to be true.
For example, if somebody says "I believe that 2+2=4", they are saying they accept as correct the statement that 2+2=4.
But also, if somebody says "I believe it will rain tomorrow", they are saying that they accept as very probably correct that it will rain tomorrow (even though the outcomes of future events cannot be known with certainty).
Some care has to be taken when people make statements about what they do not believe, however.
For example, when somebody says "I do not believe that it will rain tomorrow", it is possible that they hold the view that "it will not rain tomorrow". But it is also possible that they are only saying they do not accept that the claim "It will rain tomorrow" is certainly true or very probably true. For instance, perhaps they estimate the chance that it will rain tomorrow to be 1 in 3, which means that they think it is more likely than not that the statement "It will rain tomorrow" is false. It is also possible that they merely consider that they do not (yet) have sufficient reason to accept that the claim "It will rain tomorrow" is true.
It is important to recognise that in the second and third examples, the person who does not believe is not making a claim. The person might believe that "It will not rain tomorrow", but he has not (yet) made the claim that it will not rain tomorrow; he might go on to make that claim, or he might not. Alternatively, the person might believe "It is more likely than not that it will not rain tomorrow" but, again, he has not yet made that claim. Finally, the person might believe "I don't yet have sufficient information to decide whether it will rain tomorrow or not", which means he would be lying if he claimed to believe that it will rain tomorrow (or not rain tomorrow).
Thus, it is straightforward to interpret what a person means when they say "I believe that X is true", whereas further interrogation will usually be necessary to get to the bottom of what a person means when they say "I do not believe that X is true".
It should be clear by now that the statement "I do not believe that X is true" is not equivalent to the statement "I believe that X is false".
Depending on the claim, the passage of time might reveal whether the claim is actually true or false, or it might not. The claim "It will rain tomorrow" will be shown to be either true or false tomorrow. In the meantime, it is perfectly reasonable for somebody to wait until the truth or falsity of the claim becomes apparent. In many cases we even find ourselves in the position where we simply can't know whether a claim is true or false at this time, and in some case we will never know.
On being convinced
In light of this, it is clear that belief statements boil down to whether the speaker is convinced that a claim is true, at the time of his or her statement of belief. A person who, for whatever reason, is convinced that the claim is true (or very likely to be true), will say "I believe" it is true. On the other hand, a person who is not convinced will say "I do not believe" the claim is true, either because they believe the claim is false (or likely false) or because they are adopting a "wait and see" approach (e.g. lack of sufficient information to form an opinion, or prudence about unwisely leaping to a conclusion that might turn out to be wrong).
Ontology - the axis of belief
Ontology is the philosophical topic concerned with questions of what things exist in the world and what their nature is.
When somebody says "I believe that X is real" or "I believe that X exists", they are making an ontological statement. They are convinced that the statement "X exists" is true, or very likely to be true.
A person who says "I do not believe that X exists" is not making an ontological claim. They are saying that they aren't convinced that the statement "X exists" is true. Maybe that's because they are convinced the statement is false. Maybe it's because they are convinced that the probability that the statement is true is low. Or maybe they are adopting a "wait and see" approach and they don't want to leap to a conclusion that might turn out to be wrong. More questioning will be required to discover why they are not convinced that X exists.
Theism and atheism - definitions
A theist is a person who believes that one or more deities exist. That is, they are convinced that the claim "One or more deities exist" is either true or very likely to be true.
An atheist is a person who does not believe that one or more deities exist. That is, they are not convinced that the claim "One or more deities exist" is true. It could be that they are convinced that there are no deities. It could be that they are convinced that there is a low probability that one or more deities exist. It could be that they are adopting a "wait and see" approach and they don't want to jump to a conclusion that might turn out to be wrong.
Here's my latest crack at it, for discussion and possible debate.
Two independent axes
Agnosticism is often conceptualised or explained as a "middle ground" between theism and atheism. However, I assert that agnosticism is best understood as lying on a perpendicular axis to the theism-atheism axis. Thus, we have the theist/atheist distinction and another, independent, gnostic/agnostic distinction.
All four combinations are possible, such that it is quite reasonable for a person to self-identify as a gnostic atheist, an agnostic atheist, a gnostic theist or an agnostic theist.
About belief
To say that one believes a claim is to assert that one accepts that the claim is true or very likely to be true.
For example, if somebody says "I believe that 2+2=4", they are saying they accept as correct the statement that 2+2=4.
But also, if somebody says "I believe it will rain tomorrow", they are saying that they accept as very probably correct that it will rain tomorrow (even though the outcomes of future events cannot be known with certainty).
Some care has to be taken when people make statements about what they do not believe, however.
For example, when somebody says "I do not believe that it will rain tomorrow", it is possible that they hold the view that "it will not rain tomorrow". But it is also possible that they are only saying they do not accept that the claim "It will rain tomorrow" is certainly true or very probably true. For instance, perhaps they estimate the chance that it will rain tomorrow to be 1 in 3, which means that they think it is more likely than not that the statement "It will rain tomorrow" is false. It is also possible that they merely consider that they do not (yet) have sufficient reason to accept that the claim "It will rain tomorrow" is true.
It is important to recognise that in the second and third examples, the person who does not believe is not making a claim. The person might believe that "It will not rain tomorrow", but he has not (yet) made the claim that it will not rain tomorrow; he might go on to make that claim, or he might not. Alternatively, the person might believe "It is more likely than not that it will not rain tomorrow" but, again, he has not yet made that claim. Finally, the person might believe "I don't yet have sufficient information to decide whether it will rain tomorrow or not", which means he would be lying if he claimed to believe that it will rain tomorrow (or not rain tomorrow).
Thus, it is straightforward to interpret what a person means when they say "I believe that X is true", whereas further interrogation will usually be necessary to get to the bottom of what a person means when they say "I do not believe that X is true".
It should be clear by now that the statement "I do not believe that X is true" is not equivalent to the statement "I believe that X is false".
Depending on the claim, the passage of time might reveal whether the claim is actually true or false, or it might not. The claim "It will rain tomorrow" will be shown to be either true or false tomorrow. In the meantime, it is perfectly reasonable for somebody to wait until the truth or falsity of the claim becomes apparent. In many cases we even find ourselves in the position where we simply can't know whether a claim is true or false at this time, and in some case we will never know.
On being convinced
In light of this, it is clear that belief statements boil down to whether the speaker is convinced that a claim is true, at the time of his or her statement of belief. A person who, for whatever reason, is convinced that the claim is true (or very likely to be true), will say "I believe" it is true. On the other hand, a person who is not convinced will say "I do not believe" the claim is true, either because they believe the claim is false (or likely false) or because they are adopting a "wait and see" approach (e.g. lack of sufficient information to form an opinion, or prudence about unwisely leaping to a conclusion that might turn out to be wrong).
Ontology - the axis of belief
Ontology is the philosophical topic concerned with questions of what things exist in the world and what their nature is.
When somebody says "I believe that X is real" or "I believe that X exists", they are making an ontological statement. They are convinced that the statement "X exists" is true, or very likely to be true.
A person who says "I do not believe that X exists" is not making an ontological claim. They are saying that they aren't convinced that the statement "X exists" is true. Maybe that's because they are convinced the statement is false. Maybe it's because they are convinced that the probability that the statement is true is low. Or maybe they are adopting a "wait and see" approach and they don't want to leap to a conclusion that might turn out to be wrong. More questioning will be required to discover why they are not convinced that X exists.
Theism and atheism - definitions
A theist is a person who believes that one or more deities exist. That is, they are convinced that the claim "One or more deities exist" is either true or very likely to be true.
An atheist is a person who does not believe that one or more deities exist. That is, they are not convinced that the claim "One or more deities exist" is true. It could be that they are convinced that there are no deities. It could be that they are convinced that there is a low probability that one or more deities exist. It could be that they are adopting a "wait and see" approach and they don't want to jump to a conclusion that might turn out to be wrong.
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