I knew I would come across this problem with my wife when I started talking with her. Like Listener said, you'll just go around in circles on that one.
I chose to avoid it completely.
Instead, I focused on the Society's deliberate deception:
For my wife, I decided I would stick to one thing that could not POSSIBLY be overcome - the dishonesty of the Society in their literature.
This goes above and beyond "new light".
My wife is an extremely smart woman and researches on her own quite often. I knew she would go toe-to-toe with me on scriptures and doctrine and "new light" and could hold her own.
By sticking to dishonesty, she simply cannot refute it. The proof is in the Society's own publications. It is equivalent to catching the Society with their pants down.
My goal was that once I made inroads using the dishonesty tactic, I could THEN lead into other stuff, like "new light" and cultish tactics (we've talked alot about the cultish stuff since then).
My folders just contained notes of research - some handwritten, some typed up. Just facts listed. They also contained scans of documents.
For my 1914 folder I put a list of quotes from the WT-CDROM where they said (even in the 90's) that they predicted Christ's invisible return was going to come in 1914. Then I put a half dozen scans of the Society saying unequivocally that 1914 was Armageddon and that 1874 was the year that he had already returned. Then I put in the scan of the Watchtower where they said they never said it would "positively" be the year. Important: I left out any commentary by me or anyone else.
This folder in particular affected my wife greatly. I think I mentioned it in one of my past threads.
Then you have to think of every possible counter-argument she would make for the evidence you present to her. For instance, my wife said, "Well that is old literature, and alot has changed since then." (i.e. "new light") That is classic JW-trained mentality to divert from the issue at hand.
But it's NOT "new light"! I told her, "My issue is not that the information is old. My issue is why would the Society - even today - lie about their early predictions?" (Sticking to dishonesty.)
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I have another folder on the trinity. I printed out the quotes from the early Church fathers (where the Society misquoted them in the Trinity brochure). I also had scans of many of the publications (like the Catholic Encyclopedia) where they misquoted them to make JWs think the Catholics admit the Trinity is a flawed doctrine - when in fact they do not. I purchased these scans from a countercult ministry website. I can scan them in and send them to you if you want.
Again, I left out commentary and leading questions and let the evidence speak for itself. Again, my wife tried to divert by saying, "So you believe the trinity then?" I told her it didn't matter what I believe at this point - I am still learning. But I kept bringing it back to dishonesty, "Why does the Society see fit to misquote the early church fathers and all these secular resources if the Trinity is such an open-and-shut case?"
I did the same thing with the Cross issue. Scans of quotes taken out of context. Same questions ... "Why the dishonesty if it supposedly so obvious to the JWs that Jesus died on a stake instead of a cross?"
Also, I spent alot of lunch breaks and early morning commutes actually practicing out loud how I would present these topics to my wife. I made-believe she was sitting next to me and walked her through each folder and what I would say - out loud.
I think practicing out loud helped me alot. And each time I practiced it out loud I would make up imaginary curveball questions in my head as I was going along and would try to answer them out loud on-demand. I would even throw myself curveball questions I couldn't answer and would practice admitting I don't know that answer but would like to research it more.
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I firmly believe putting things before them that cannot be refuted, like the dishonesty of the publications - is the key.
It also KILLS the NEW LIGHT crap because that involves giving the Society the benefit of the doubt. But you cannot give someone the benefit of the doubt that has lied in their publications.
You have just cut off your opponent's argument at the knees.
-ithinkisee