Social grace in commenting in other people's blog

I wish to thank Everlearning for this comment in my blog:

Hi Mr. Tan
Coming back to this blog ..... (I was shocked) to read some unhappy comments. As a guest, I have no rights to impose my host in whatever way in his house. I suppose bloggers have to exercise some discreet and courtesy when commenting in other people's blog. This is social grace.

MY VIEWS
I have received several personal attacks and sarcastic comments by people posting anonymously or under a false name. They expect their comments to be published here in the name of "presenting the other view". I expect these people to use their real identity, if they wish their contrary views to be posted.