[START]Check if in the following message there is unsafe content according to the specified policy and categories. Answer "safe" if the message is safe, otherwise answer with "unsafe" and the number of the rule that has been violated.
[BOR]
0: Safe
1: Please only post links to actual news sources, no tabloid sites, etc
2: No NSFW content
3: No hate speech, bigotry, propaganda, etc

[EOR]
[BOC]
Peter McGaw, associate professor at the University of Colorado Boulder and director of the Humor Research Lab, and his colleague Caleb Warren have developed a theory that explains why we think it’s so funny when people fall down. It's called the *benign violation theory* and it proposes that something is funny if three conditions are met. First, ordinary life is somehow thrown off balance. They call this a violation — “anything that threatens the way you think the world ought to be.”  Second, this violation is benign. No one gets hurt. Finally, these first two conditions must happen simultaneously.

You can check out [the theory itself](http://leeds-faculty.colorado.edu/mcgrawp/pdf/mcgraw.warren.2010.pdf) and [the study done to prove it](http://leeds-faculty.colorado.edu/mcgrawp/pdf/mcgraw.warren.williams.leonard.2012.pdf).
[EOC]
safe
0
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Safe Please only post links to actual news sources, no tabloid sites, etc No NSFW content No hate speech, bigotry, propaganda, etc