in reply to Ignoring nodes
A prime example would be posting "Python is so much better than Perl!" It wouldn't matter whether the poster really believed that; he would write it because he knows it'll stir things up.
Someone who responds to such a post is said to have been trolled.
Also see troll in the Jargon File.
There is no Extraterrestrial life
There aren't any suitably capable Extraterrestrials
Interstellar travel is too difficult
We're too uncool / not worth the trouble
What do you mean they haven't visited?
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