Oh, there have been plenty! But Mark Shea has had some really good stuff on it, including this post from today, where he lets us in on how Pullman, anti-Christian and fervant atheist, could wind up with certain Christian themes sneaking into his novels, such as the beautiful nature of sacrificial love.
In the Harry Potter novels, Christian elements and images are found everywhere, because the author had every intention of telling a fundamentally Christian story. She was trying, for all her faults as a writer or philosopher, to cooperate with grace. In His Dark Materials, Christian elements creep in only because Pullman could not successfully block out the light of Christ completely, despite his best efforts to do so. By way of analogy, Satan cannot rid himself of his own being, intelligence and will (all gifts of God and testimonies to His glory) without ceasing to be altogether. This hardly means that Satan "means well". Evil is *always* parasitic on good and must always, to some degree, pay tribute to it. Pullman's evil work is no exception. That does not mitigate the fact that it is evil.
That is one of the best explanations I've read on this! If I'm feeling better and stronger spiritually, I might pick up the books sometime just to see. But I make no plans on giving them to my children, as I think giving them such blatantly anti-Catholic books would only serve to confuse their young minds. (For the record, I'm not afraid of them hearing or reading things that are not Catholic, but I limit it severely right now, when they are still developing their consciences. When they are older and better equipt to deal with themes such as these, I see no reason to keep those ideas from them. After all, if I insulated them from anything non-Catholic, we'd rarely leave the house, and they certainly wouldn't be involved in most of their activities.)
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