Since it appears that you grew up in a pluralistic society then I have no idea why you considered everyone different then you to not be a good person and feel you were never exposed to the idea that they possibly could be a good person. Considering that Jesus (Matthew 25:40), Paul (Romans 2), Nephi, Benjamin, Alma, and Moroni all say that it is action more then belief that defines who is saved, who has faith, and who is good, happy and healthy then I don't know how it was a shocking revelation that those who do not have the law but that act by nature according to law are just as much blessed as those that have the law.
I fail to see how blood atonement, Adam-God, racist theology, and polygamist theology gave you the slightest impression that the Journal of Discourses was a good source of doctrine. It is my personal experience that generally those that spend the most time reading it are those least familiar with the gospel, on either end of the spectrum. The biggest fans of the Journal of Discourses seem to be those that are trying to prove the church wrong and those that are seeking "deep" doctrine while ignoring the weightier parts of the gospel, by which I mean those that try to square Adam-God statements or that speculate on the location of the ten tribes or Kolob.
For instance nearly everyone that has taken the time to figure out what Christians say of God in their arguments for God and what the D&C says on the subject quickly realize that the two are wholly incompatible. That those beliefs on God and the arguments in favor of those beliefs are mixing Greek philosophy with scripture to synthesis a new belief. Not that members of the church are not also guilty of mingling the philosophies of men with scripture, that is a very common occurrence as you note with "what is taught in the chapel and the dinner table", me, I tend to focus on the current authorized messengers from God and the Holy Spirit as I feel that is what I have been instructed to do.
Hey, people make mistakes. That it's fairly easy to come to erroneous conclusions on these topics should be evident from the JoD itself.
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A list of some posts that are pretty awesome
I recommend the major sequences to everybody, but I realize how daunting they look at first. So for purposes of immediate gratification, the following posts are particularly interesting/illuminating/provocative and don't require any previous reading:
More suggestions are welcome! Or just check out the top-rated posts from the history of Less Wrong. Most posts at +50 or more are well worth your time.
Welcome to Less Wrong, and we look forward to hearing from you throughout the site!
Note from orthonormal: MBlume and other contributors wrote the original version of this welcome post, and I've edited it a fair bit. If there's anything I should add or update on this post (especially broken links), please send me a private message—I may not notice a comment on the post. Finally, once this gets past 500 comments, anyone is welcome to copy and edit this intro to start the next welcome thread.