By not believing in the existence of God but not knowing if God exists or not. Taking the origin of the word literally. I don't accept what people say it's proof of existence or non-existence.

This page might answer some of your questions. [agnostic.com]

That's atheism. Agnosticism simply means an individual KNOWS he doesn't know if god exists, or not.
Atheists are always saying there's no evidence there IS a god, but agnostics answer, there's no evidence there ISN'T.

I am an atheist because I have not seen evidence that supports the god(s) hypothesis, i.e. that they are real. I am an agnostic because I am not 100% sure that I am correct. Could there be some race of beings out there, somewhere in the universe that have evolved to a point that they would fit our description of a god? I'm not sure if we can ever clearly say "no." We can only claim that "we haven't found any evidence to support that statement yet." The evidence I have seen boils down to "I don't understand, therefore god," some sort of philosophical exercise that doesn't inform observable reality, or "I just feel that it's real" which is no evidence, only the same intuition that leads people to think a bowling ball will fall to the earth faster than a tennis ball when dropped under the same conditions.

The existence of human failings is because of....humans

IF you believe that an all powerful being that created the universe chose an obscure middle eastern tribe to be his chosen people and helped them to defeat their enemies and populate lands promised to them then you are delusional.
Read the pentateuch with an open mind and it is apparent that this polytheistic tribe gradually adopted monotheism to aid their acquisitive behaviour,. so why be agnostic unless of course if you believe that some of the Hindu,Norse,Roman,Greek, other gods may exist.

I'm always thinking in terms of the old guy with the beard.

I don't rule out the idea of god in the religions of the East.

I believe there is no God. It seems self-evident to me.

I’m not agnostic. I am as certain of the non-existence of god as the sun appearing to rise in the eastern sky tomorrow. One part of the definition of agnostic is the belief that nothing is known or can be known beyond material phenomena - and I don’t hold that belief. It seems to me our thoughts are non-material and ideas like kindness, neglect, justice, betrayal really exist, are knowable and non-material.

If I find myself in a discussion about atheism and/or agnosticism I usually trot out these arguments:

1. I cannot prove to 100% certainty that there isn’t an elephant running loose in our city but the absence of frantic Facebook posts, piles of elephant poop, the lack of any circus being in town recently gives me enough evidence to make a determination.

2. if God, by definition, is omnipresent then there is no way to prove existence because one would need to experience or know the condition of God not being there. To know if God exists the condition of not-God is required (i.e. if all the text on a page is bold how would you know? Contrast with non-bold text is required).

However, I have had what I consider to be spiritual experiences where I truly felt the knowledge of the implications of the reality of the interconnectedness and interdependence of all beings on the planet, especially the human ones (to whom I feel a great affinity). I’ve also had road rage and felt significantly less connected.

I see all religions as pretentious and superstitious nonsense sanctioning and requiring a shared obsessive compulsive disorder. They feel the need to believe that certain hand gestures or body postures will conjure or ward off spirits or judgement. The texts religions produce serve to justify the superstition and group OCD.

I highly doubt any god exists, but I'm open to actual evidence.

The vast and wondrous unknown. "I do not know" is the beginning of knowledge.

There is little, if anything, we know at all in this life and this universe, with absolute, 100% certainty. Part of this is due to human fallibility and the fundamentally subjective nature of human knowledge and awareness. Therefore, we have to rely on probabilities, or what makes the most sense to believe.

Atheists or agnostics refer to God (or the concept of a god, or gods) when they assert what they believe, or don't know. That seems fairly clear to me. They are constantly saying why they don't believe in posts on here in the first person. I see that all the time.

I like reading everyone's responses to this post. Very interesting conversation going on.

With that said, I consider myself to be an Agnostic Atheist. Agnostic because I feel that I could not prove nor disprove the existence of a deity or deities. However, the Agnosticism kicks in when I see—another poster has mentioned this in the comments and I gave it a thumbs up—poverty, mental illness, and other negative parts that exist in humanity. And if there is a god, then it is not one who cares about mankind. Therefore, it doesn't deserve any type of recognition anyway.

But yeah, the whole proof thing and that there are so many questions left unanswered is why I am more of an Atheist.

The only thing I'm agnostic about is the creation of the Universe. Furthermore, I don't ascribe the binary thinking of god or no god that you mention in your post. There are other possible options.

I am of Freethought, a Freethinker if you will. I'm thinking that is most true of most Aagnostic.com.

Mostly "I detest Christians" i guess?

IF,,,,there was a "god" then he is doing a crappy job. I am experiencing heart failure. Will have my chest cut open, because "god" made a mistake.

I had a student in class once tell me that Siri knew everything.

I asked him to ask Siri what the meaning of life is.

Siri got confused and never answered. The whole class erupted in laughter.

(I just googled it, and google sent me to the wiki entry describing what the question "what is the meaning of life?" entails. Wow. That's really life-changing, google.)