I'm an INTP and I basically have never accepted the distinction people like to make between atheism and "agnosticism." Defining atheism as "a positive belief that God does not exist" just doesn't fit the majority of people who consider themselves atheists.
"Agnosticism," to me, would mean that a person has seen an equal amount of equally compelling evidence suggesting the existence and non-existence of a deity, and was thus unable to confidently state which of the two positions was most probably correct. Atheism, as the term is used by most atheists, simply means that explanations for various phenomena that neither require nor suggest divine influence are supported by a much greater preponderance of evidence and logic than any claim that the same phenomena are of divine origin.
I dislike the shrillness of tone in Richard Dawkins' The God Delusion as much as anyone, but his definition of atheism is a much more accurate description of the outlook most atheists take--namely, that although an omnipotent supernatural force is certainly a theoretical possibility, examination of any claim about such an entity leads to the conclusion that the probability of its being true is so slight as to warrant no further consideration.
I'm an atheist. I say this surely and proudly. I do not subscribe to some "religion of science," because science is not a dogmatic set of assertions about reality. Science is a method of investigating reality and evaluating claims made about it. Although I may prefer, based on past experience, to rely on scientific methods of inquiry to the exclusion of any religious or "spiritual" approach to the same subject(s), this does not mean that my attitude toward science is equivalent to a religious person's attitude toward their religion. My "belief" that species arise through mutation and natural selection or that it is unlikely a man genuinely rose from the dead is not equivalent to a fundamentalist Christian's belief in a 6-day Creation or the resurrection of Christ. I "believe" it is unlikely anyone will ever find compelling evidence to support either of the latter claims; the fundamentalist Christian believes that they must both be true, regardless of any evidence to the contrary.
I would hope an intelligent and honest person would be able to understand the distinction I am making, and I only write this to clarify a common misunderstanding. None of this is intended as argumentative, nor should it be taken as such.