"Argument Timing", by Randall Munroe, licensed under Creative Commons Attribution-NonCommercial 2.5 License
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Of course, everyone has their own profile. There are morning arguers, hangry arguers, meal-time arguers, late-night arguers, and people who get in a meta-argument over what their argument timing is, dredge up examples of past arguments, and end up fighting over THOSE again as well.