Not equivalent, but comparable yes. The online forum is real life without the facial, nonverbal information. The absence of that nonverbal info does not imply that all social norms are different too. Behind the keyboards are sitting real people with real emotions.

Your remark about unsolicited email is in itself correct, but is it valid in this context? Not in my opinion. A better metaphore is regular email. Sure, you can decide to ignore your regular email, but in time people will start to criticize you for that behavior.

>YOU'REEEEE OUTTTAAA HEERRRREEEE ...
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>Only kidding.
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>The error of your argument is that you consider online forums to be equivalent to real life, face to face interactions in a home or office. They are two different environments and have their own social norms and ways of doing things.For example, I don’t respond (normally) to unsolicited email and I don’t feel I need to tell them why I'm not responding.
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>>Take the principle to your household or to your workplace. Suppose you no longer will (want to) hear what certain others are telling you and as a consequence you also don't react to them. Suppose you also have not informed them about this. You'll be in trouble within one day. What's hilarious about that.
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>>>Although I haven't used it (yet) the purpose of a filter is to filter, not also to inform of the filtering. If the person wants to inform the twitted person they can do so using various other techniques. I thinks the whole discussion is hilarious.
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