I can't second this statement enough. How many people hit 'send' or 'submit' without thinking for a moment, re-reading, and then editing because something just doesn't sit right? With me it is spelling typos, yet they still manage to slip in there (part of the 50wpm tested typing speed using three fingers and a thumb...) I know I try to put myself on the receiving end when reading back what I type. Unfortunately by my editing and RE-editing, I sometimes veer from the point I was trying to make.
Unfortunately the Internet DOES add an air of protection and anonymity. How many people post something malicious and then bump into that same person a week later and feel ashamed by what they had said, even if the other person isn't even aware of the slight...How many of us have posted and SHOULD feel ashamed but don't??
Two things that were drummed into me as a child (yes, back in the days when mom used a belt!)
1) Treat others as you want to be treated yourself ("Do unto others"-basic biblical principle)
2) And stand up for the downtrodden or those unable to defend themselves.
One I would like to add is 'What goes around comes around'.