In the midst of "Chicken or Beef?" we find Lorelai and Rory at Luke's talking about how Rory had just bumped into Dean and invited her to his wedding the next day. Rory isn't sure whether to go or not, when Lorelai comes to the conclusion that it was fate that made her and Dean run into each other (or something like that) and Rory considers going. Then Luke intervenes saying that there is no such thing as fate, Tarot, astrology... Here's the slip up, in the next season episode "Written in the Stars" when Luke and Lorelai are on their first date Luke shows Lorelai a horoscope she gave him the day he met her. So much for being a non-believer...