Agnosticism is the philosophical view that the truth value of certain claims — particularly theological claims regarding metaphysics, afterlife or the existence of God, god(s), or deities — is unknown or (possibly) inherently unknowable. Agnosticism is not to be confused with religious views opposing the doctrine of gnosis and Gnosticism — these are religious concepts that are not generally related to agnosticism. Agnostics claim either that it is not possible to have absolute or certain knowledge or, alternatively, that while certainty may be possible, they personally have no knowledge. Agnosticism in both cases involves some form of skepticism.

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• Agnostic: one who's extreme skepticism even keeps them from being an atheist.
  • Derek Abbott, quoted in The Wickedictionary (2009).

• I say that I am an agnostic. People think that's pusillanimous and covering your bets. But it's not based on any belief or yearning for an afterlife but on the fact that we actually know so little about the cosmos. It is a tribute to the complexity and, at our present stage of development, the unknowability of the universe.
  • Martin Amis, in "The New Amis" in The Telegraph (13 May 2000)
• Belief is otiose; reality is sufficiently awesome as it stands.
  • Martin Amis, "The voice of the lonely crowd", The Guardian, 1 June 2002

• I am a skeptic about everything, including God and atheism. I am not certain about issues of cosmology. Sometimes I believe that our universe is the result of random forces. Other times I believe that there must be some order or purpose, though I do not begin to understand what or who it could be. I do not expect that these cosmic doubts will ever be resolved in my mind. I am more certain that the miraculous stories that form the basis of most religious beliefs are myths. Yet I respect the Bible and enjoy reading and teaching it. Indeed, I find it even more fascinating as a human creation than as a divine revelation. I consider myself a committed Jew, but I do not believe that being a Jew requires belief in the supernatural. When I attend synagogue, as I often do, or conduct Sabbath, Passover, or Chanukah services at home, I recite prayers. I am comfortable with these apparent contradictions. I am part of a long tradition that links to my heritage through the words and melodies of prayer. Indeed, it is while praying that I experience my greatest doubts about God, and it is while looking at the stars that I make the leap of faith. But it is not faith in the empirical truths of religious stories or in the authority of hierarchical religious organizations. If there is a governing force, He (or She or It) is certainly not in touch with those who purport to be speaking on His behalf.
  • Alan Dershowitz, in "Taking Disbelief out of the Closet" in Free Inquiry, Vol. 19, (Summer 1999)

• One should not have the arrogance to declare that God does not exist.
  • Umberto Eco, quoted in "Belief or Nonbelief? : A Confrontation By Umberto Eco and Cardinal Carlo Maria Martini" in The Los Angeles Times (18 March 2000)

• I do not consider it an insult, but rather a compliment to be called an agnostic. I do not pretend to know where many ignorant men are sure — that is all that agnosticism means.
  • Clarence Darrow, Speech in Dayton, Tennessee (13 July 1925), defending John T. Scopes, on trial for teaching Darwinian concepts of Evolution.

• When I reached intellectual maturity, and began to ask myself whether I was an atheist, a theist or a pantheist, a materialist or an idealist, a Christian or a freethinker, I found that the more I learned and reflected, the less ready was the answer. The one thing on which most of these good people were agreed was the one thing in which I differed from them. They were quite sure they had attained a certain "gnosis" — had more or less successfully, solved the problem of existence; while I was quite sure that I had not, and had a pretty strong conviction that the problem was insoluble.
  • Thomas Huxley, in 'Christianity and Agnosticism: A Controversy (1889)

• I took thought, and invented what I conceived to be the appropriate title of "agnostic." It came into my head as suggestively antithetic to the "gnostic" of Church history, who professed to know so much about the very things of which I was ignorant. To my great satisfaction the term took.
  • Thomas Huxley, in 'Christianity and Agnosticism: A Controversy (1889)

• Agnosticism is not properly described as a "negative" creed, nor indeed as a creed of any kind, except in so far as it expresses absolute faith in the validity of a principle which is as much ethical as intellectual. This principle may be stated in various ways, but they all amount to this: that it is wrong for a man to say that he is certain of the objective truth of any proposition unless he can produce evidence which logically justifies that certainty. This is what agnosticism asserts; and, in my opinion, it is all that is essential to agnosticism.
  • Thomas Henry Huxley, in "Agnosticsim" published in The Nineteenth Century (February 1889) ; also in Christianity and Agnosticism (1889)

• Agnosticism simply means that a man shall not say he knows or believes that for which he has no grounds for professing to believe.
  • Thomas Henry Huxley, quoted in The Great Quotations‎ (1960) by George Seldes, p. 345

• It's important to abolish the unconscious dogmatism that makes people think their way of looking at reality is the only sane way of viewing the world. My goal is to try to get people into a state of generalized agnosticism, not agnosticism about God alone, but agnosticism about everything. If one can only see things according to one's own belief system, one is destined to become virtually deaf, dumb, and blind.
  • Robert Anton Wilson, in "Robert Anton Wilson: Searching For Cosmic Intelligence" - interview by Jeffrey Elliot