If you cannot use the terms "Nazi", "Stalinism", "socialism" and "communism" in a sentence correctly, or cannot differentiate one from the other, please do not engage in political discourse.
There is no mercury in flu shots. The flu shot is bits of a dead virus and will not give you the flu. Nor will it give your unborn child birth defects. If you cannot internalize these simple bits of scientific fact, please do not engage in discussion of how evil flu shots are.
It's not "hermaphrodite." It's "intersexed." That's the correct, accepted, professional term. If you can't bring yourself to be correct, please don't talk about South African runners to me.
Your opinion on medical issues is automatically downgraded in my eyes if you are a young-Earth creationist.
Your opinion on *everything* is automatically downgraded if you cannot accurately define "theory," "hypothesis," and explain briefly what the differences between the two are.
If you begin a sentence with the words "All women..." and if that sentence ends with anything other than "are fantastic", don't be surprised if I end that sentence for you with a heel to your instep.
Thank you, and good night.