The word "mystery," in this context, can mean (a) something we don't currently understand, or (b) something we will never understand. Which meaning are you using? Ghs Neither, I think that for some Christian thinkers it doesn't carry primarily a cognitive sense, but carries primarily an existential one. An "existential" sense is that one that speaks directly to a person's "sense of life" in the Randian sense. It is more than merely emotional. I don't think that the sense with which Rand looked at the scycrapers of New York and wept is merely emotional. (A person could feel momentarily emotional attraction for someone. But if that wouldn't be deep, that wouldn't be "existential"). Existential is deeper than merely emotional. I think that in the "Brave New World", if you remember it, the main character, mourns that sex has lost its mystery in the "modern society", that sex is "merely physical". Maybe he doesn't use that term actually, that's my way of putting it. Or again, "The insoluble mystery" (story number eight) by Chesterton is indeed an apologetic work on christianity (as it seems to me) - then what is the argument it makes? I think it argues that there is some "sense of sacredness" without which questions like "Why not desecrate a corpse?" cannot be answered. So "sacredness" is an emphasis on values, in this context. I think that most atheists whom I have read miss this important sense of "faith". But having said this, I must really shut up. I sense that atheists don't get something about religion, and then a missionary zeal arises in me (not really being a religious person myself). I have read your book "The case against god", though some time ago, and not with the attention it deserves.