""Agnostic" is a much more recent word than "atheist", coined by Thomas Huxley in 1869 to mean "without knowledge of God" and acquiring the usage of "being doubtful about the existence of God.""

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I do not expect that the mere fact that I was once an evangelical apologist and now see things differently should itself count as evidence that I must be right. That would be the genetic fallacy. It would be just as erroneous to think that John Rankin must be right in having embraced evangelical Christianity since he had once been an agnostic Unitarian and repudiated it for the Christian faith.

— Robert M. Price