Not being a Christian I sometimes feel guilty about celebrating Christmas. I love the holiday cheer, Santa Clause, evergreen trees in your living room, and the overall sense of warmth and compassion that most people exude. Turns out, I've been worrying unnecessarily. Massimo Pigliucci has straightened me out. There are many pre-Christian traditions that are a cause for celebration. To find out what they are, you'll have to read his blog.