Agnosticism is the view that the truth, or measurable value, of certain claims, especially claims about the existence of any deity, but also other religious and metaphysical claims, is simply unknown or unknowable. Faith, by definition, is belief in that which cannot be otherwise proven.
Agnosticism can be defined in a variety of ways, and is sometimes used to indicate doubt in, or a skeptical approach to, a given issue. In some senses, agnosticism is a stance about the differences between the belief in, and knowledge of, something rather than about any specific claim or belief itself.
Thomas Henry Huxley, an English biologist, coined the word agnostic in 1860. However, earlier thinkers and written works have promoted agnostic points of view. Among others they include Protagoras, a 5th-century BCE Greek philosopher, and a creation story in the Rigveda, an ancient Hindu religious text. Since Huxley coined the term, many other thinkers have written extensively about agnosticism.
Demographic research services normally, and completely incorrectly, list agnostics in the same category as atheists and/or non-religious people. Some sources use agnostic in the sense of noncommittal. Agnosticism often overlaps with other belief systems. Agnostic theists identify themselves both as agnostics and as followers of particular religions, viewing agnosticism as a framework for thinking about the nature of their belief, and their relation, to revealed or known truths. Some non-religious people, such as author Philip Pullman, might be considered both agnostic and atheist.
Thomas Henry Huxley defined the term thus: “Agnosticism is not a creed but a method, the essence of which lies in the vigorous application of a single principle… Positively the principle may be expressed as in matters of intellect, do not pretend conclusions are certain that are not demonstrated or demonstrable.”
I include Agnosticism here, in this list of religions, not because it is a religion but, rather, because so many people mistakenly think it is. The above information may help them get closer to the truth.