AgnosticGuy
Open-minded skeptic
This is a lingering issue but I will propose a few mechanisms for how someone can be an agnostic without fitting the atheist and theist label.
Cognitive reasons
A person who has conflicting or contradictory beliefs can not be said to be atheist or theist since those labels involve a 'consistent' belief about God's existence (ie God exist= theism or God does not exist = atheism). Inconsistent beliefs can arise when a person accepts that there's evidence for both sides of an issue which means that the truth of the issue is not known, or at least not fully. This could play out when a person forms a belief that God exist based on evidence/reason X (first cause argument, etc) and then later comes across another argument/reason/evidence for why God doesn't exist and the person accepts and believes it's valid. The beliefs are based on separate reasons but lead to conflicting conclusions which the agnostic is not able to reconcile just as with any other complex/unknown issue that has support for both sides.
Now some may say that in theory this can happen but is not practical. I of course would disagree with that not only because we form belief based on evidence and it's possible for there to be evidence for both sides of an issue, but I'll also proposed two other mechanisms.
One way that contradictory beliefs can exist is through mental compartmentalization. That is that we is that we tend to compartmentalize different ideas/beliefs in the brain or better way to put it:
Source: http://www.scientificamerican.com/article/the-minds-compartments-create-conflicting-beliefs/
Another way to have contradictory beliefs is by having 'split brain syndrome'. This can occur in those who have had a corpus calloscotomy which is surgically disconnecting the right brain from the left brain. This actually can lead to more than just contradictory beliefs but also to contradictory behaviors which is further described in my source below.
Source: http://www.nature.com/news/the-split-brain-a-tale-of-two-halves-1.10213
Source: https://www.psychologytoday.com/blog/the-superhuman-mind/201211/split-brains
I'm bringing up this issue because I feel that agnostics tend to be misunderstood and part of the problem is that many want to characterize the agnostic as being on one side or the other. Some agnostics tend to hold views or be extremely open to views on both sides so rather than frustrating yourself (certain atheists or theists), it would be better to not conclude which side I would be on based on one position that I have.
Cognitive reasons
A person who has conflicting or contradictory beliefs can not be said to be atheist or theist since those labels involve a 'consistent' belief about God's existence (ie God exist= theism or God does not exist = atheism). Inconsistent beliefs can arise when a person accepts that there's evidence for both sides of an issue which means that the truth of the issue is not known, or at least not fully. This could play out when a person forms a belief that God exist based on evidence/reason X (first cause argument, etc) and then later comes across another argument/reason/evidence for why God doesn't exist and the person accepts and believes it's valid. The beliefs are based on separate reasons but lead to conflicting conclusions which the agnostic is not able to reconcile just as with any other complex/unknown issue that has support for both sides.
Now some may say that in theory this can happen but is not practical. I of course would disagree with that not only because we form belief based on evidence and it's possible for there to be evidence for both sides of an issue, but I'll also proposed two other mechanisms.
One way that contradictory beliefs can exist is through mental compartmentalization. That is that we is that we tend to compartmentalize different ideas/beliefs in the brain or better way to put it:
Source: https://en.wikipedia.org/wiki/Compartmentalization_(psychology)Compartmentalization is an unconscious psychological defense mechanism used to avoid cognitive dissonance, or the mental discomfort and anxiety caused by a person's having conflicting values, cognitions, emotions, beliefs, etc. within themselves. Compartmentalization allows these conflicting ideas to co-exist by inhibiting direct or explicit acknowledgement and interaction between separate compartmentalized self states.
Source: http://www.scientificamerican.com/article/the-minds-compartments-create-conflicting-beliefs/
Another way to have contradictory beliefs is by having 'split brain syndrome'. This can occur in those who have had a corpus calloscotomy which is surgically disconnecting the right brain from the left brain. This actually can lead to more than just contradictory beliefs but also to contradictory behaviors which is further described in my source below.
Source: http://www.nature.com/news/the-split-brain-a-tale-of-two-halves-1.10213
Source: https://www.psychologytoday.com/blog/the-superhuman-mind/201211/split-brains
I'm bringing up this issue because I feel that agnostics tend to be misunderstood and part of the problem is that many want to characterize the agnostic as being on one side or the other. Some agnostics tend to hold views or be extremely open to views on both sides so rather than frustrating yourself (certain atheists or theists), it would be better to not conclude which side I would be on based on one position that I have.