Most would define agnosticism as the view that the truth of certain claims (especially claims about the existence or non-existence of any deity, but also other religious and metaphysical claims) are unknown or unknowable. Simply restated, man cannot rationally have sufficient knowledge to either prove or disprove the existence of one or more religious deities, if any. As such, agnosticism is not a statement of either belief or disbelief. It is simply a statement of a basic ignorance of the facts.
While I agree with this proposition, I also believe that the definition of my state of disbelief can vary with the way the question is asked and by whom. If you are a rational person and ask me if I believe in any deity, defined as a power higher than human, I will reply that I cannot know with certainty about that which I am not qualified to understand. If I am feeling less formal, I say instead that I simply do not know enough to recognize god when I see her.
At least, those are the general tones of my answer if I am asked by a fellow unbeliever of whatever stripe. Within the confines of disbelief in the existence of gods, there is some room for reasoned discourse; we can have a rational discussion about, for example, whether or not we are atheists or agnostics. We can talk about the replacement of religious morals with secular ethics. There are a lot of subjects on the table.
However, when asked by a believer if I believe in god, I am able to give a more definite answer. Without a shadow of a doubt, I do not believe in the god they are asking about, almost always a very specific god. Because of my geographic location, I am generally being asked whether I believe in the Christian god, which is a very specific form of human delusion, involving a white-bearded illusion in the sky, all-powerful, all-knowing, and completely without conscience. I could similarly describe other gods in other locations, and so can you.
In these cases, I respond that I am an atheist, pure and simple. That is to say, I do not believe in the god of the person asking the question. All of those gods throughout the world were made up by human beings in order to control other human beings, generally by telling them that if they will just have faith and follow orders, they will never have to die. Human beings being what they are, a large percentage do not have the courage to face death (theirs or that of others), and are therefore willing to be deluded by religion. For them, belief in a lie is easier than belief in the plain truth, and they seek the easiest path.
There is no room for discussion with most such people. In the end, their arguments come down to “faith,” which is to say they believe in the magic offered them by their religion, again generally because, at the end of the day, they do not wish to ever become totally and completely dead. That is clearly irrational, if hopeful, and there is no basis for discussion.
That describes a large percentage of believers in one god or another. There is another group that mainly belongs to a religion and attends church because of peer pressure. They have been told often enough that religion is the only right way to live, and they therefore pretend to believe in order not to be looked down upon by the believers around them. Or because they can make business contacts at church, or perhaps find a new girlfriend.
That group will be pious when around the pious, or in view of the pious, but will generally not discuss religion in any other setting because they have never taken the time to understand it. They know what they were taught in Sunday school and it is just easier to go with the flow than to question what they have been told. In a discussion with an intelligent unbeliever, they will blow hard and bluster at first, but will soon begin to panic under the force of facts that they do not know enough to try to refute. This group of easily herdable mental cows is probably more numerous than are zealous believers. Since they have no real religious convictions, they generally do not start religious conversations.
None of these people are necessarily bad people. They are just people who have been deluded by the fear of death, or people afraid that their deluded peers will cause them problems if they appear not to be similarly deluded. Subtract religion from their lives, and you would find people much like rationalists, with all of our flaws and strengths.
In the end, it does not matter if I am thought of as an agnostic or an atheist. On the one hand, I do not believe in the obvious lies and magic of organized religion, and on the other I know that I do not know enough to recognize any entity that is vastly superior to mysel, that is to say, a god.
I guess that I am a little bit of each.