Someone who believes that knowledge is not possible for themselves, some to different extents. They may believe that knowledge is possible, but paradoxically, it's impossible for them to know. While one will confine this to the metaphysical, most famously, regarding the existence of God, others will believe that they can know nothing at all, as not even their senses can be trusted.

Agnostics are often well-educated, and even more often do they see themselves as such. An agnostic, by virtue of their belief, typically sees themself as a very skeptical and critical person, and indeed, they usually are. They are often more intelligent on average than those who believe they know things, or at least, so the stereotype goes. Because of this, they often develop a sense of superiority, by which they can logically and rationally transcend the arguments of less-intelligent theists, who tend to be the most vocal ones.

An agnostic esteems above all else the scientific method. It is the infallible absolute of the agnostic. Everything must be empirically demonstrable to an agnostic, or it cannot be known to exist. A typical argument an atheist would use against a theist would be: "Since you cannot prove the existence of your God, how do you know that he exists?"

An agnostic attempts to apply empiricism to absolutely every aspect of reality. A thing does not exist unless it can be "scientifically proven". A modern understanding of science is the typical rhetoric of the agnostic.
Theist: "Do you believe in God?"

Agnostic: "I do not, because it is impossible to prove the existence of God. In fact, I do not believe it is possible to prove the existence of anything, as everything we've known is a product or our subjective consciousness."

Theist: "Are you sure?"

Agnostic: "Yes, I am 100% sure."

OR

Agnostic: "If a thing cannot be proven scientifically, there is no way to know that it exists"

Philosopher dude: "But you are assuming the existence of knowledge, which in itself is a totally abstract concept that is entirely unprovable by those means. If you are to apply the scientific method to every facet of knowledge, with our current understanding of perception and cognition, it would be impossible to trust your own senses, and everything would be unprovable, and hence, you could know nothing at all, including the validity of the scientific method."

Agnostic: "Any ideas of yours cannot be empirically proven, so I need not listen to you."

Philosopher dude: *facepalm.
by Philosopher dude December 27, 2010

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Someone who believes that the existence of god can neither be proven nor disproven, or is completely unknowable at this point. An agnostic makes no assumptions regarding a god's existence.

An agnostic is also a "weak" atheist, one who is absent of belief in god, but also absent of a non-belief in god.

Common belief dictates that agnosticism is more rational than "strong" atheism, but by this logic, the only "rational" belief would be one of extreme philosophical skepticism in regards to everything, as it is impossible to prove or disprove something with 100% certainty. I doubt you would find many theistic agnostics, however, who are agnostic in regards to something like the existence of fairies in their backyards. It can therefore be argued that some agnostics are inconsistent in their beliefs.
Agnostic: "Gods existence can neither be proven nor disproven, or is unknowable at this point."
Strong Atheist: "God does not exist."
Theist: "God does exist."

Christian Fundamentalist: "lol stupid agnosticz what kind of word is that anyway? nywayz, enjoy ur eternity in hell while i'm up in heaven with baby jesuz lusers!!!!!11one"
by SOKFHES8584 September 23, 2006

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An atheist without balls
Hi. i'm an agnostic because i dont believe in god but wont admit it.
by GangstaSwag January 03, 2010

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A lazy atheist
someone who cant make up their freakin mind
Kyle was too lazy to think up an argument to the Is there a God? question so he just called himself agnostic
by Blyan May 13, 2010

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An atheist without balls
"My friend Toby is really an atheist but he's scared that he might be wrong so he says he's agnostic"
by The Nard-Dog September 10, 2009

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A person who does not know whether to believe that God or a higher power exists or not.
Basically, an atheist without balls.
There is no proof for or against a higher power, so I guess you could call me agnostic.
by theguzmanbang August 15, 2009

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Pussy Version of Atheist
Chris: You can't prove God.
Ben: We're at religious war you Agnostic pussy as bitch choose your side: either there's a god or there isn't a god.
by jupeter July 24, 2009

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A scape-goat word that people use when they are too afraid of what society will think of them for saying that they don't believe in a "god".
Uber Religious Friend: "Hey Buddy, wanna go to church with me instead of hanging out and playing video games today?"

Guy who doesn't believe in god at all but is scared of what his friend will think: "ooh, I'm agnostic.. I don't think I'll go today but maybe next time!" (knowing he'll never go because he doesn't believe in god AT ALL)
by GivUpYerGhost May 24, 2009

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