None of these suggestions will (probably) work. Age blocks generally lead to lying about one's age, and a maturity questionnaire would be too tedious to be done correctly. It's probably best to accept the fact that a serious debate could not happen here. It's not that bad, as this place is pretty much a gaming forum, and, to be totally honest, i haven't met a whole lot of mature gaming people. I'm not saying that their aren't any, but still. On a final note, maturity is also measured only by the one doing the measuring. In other words, in the eye of the beholder.