We know that is at least welcome to provide a reason (and preferably some reference) when providing an answer. I am glad that we are not Nazis about this, and a strict format is not required.
I found the following "reasons" supporting that an answer is good:
- dictionaries;
- grammar books / sites;
- Google n-gram;
- "I am a native English speaker"
- "People usually say..."
- and the best of all: "I am not a native English speaker and I make countless mistakes while answering (sometimes misunderstanding big time the question), but I have the nerve and the energy to answer and to defend my answer."
When there is a consensus about the answer, everything is fine. But what happens when there is no consensus?
Main question(s): Which is "the ultimate" reference for the English language? Is there any "ultimate" reference? We need this when deciding / judging which answers are best.
Which dictionaries are "official"? Which should be trusted more than others? As I see it, a dictionary is a book written by somebody, which can ultimately have mistakes (intentional or not). Does a new slang become proper English if it appears in only one dictionary? In any dictionary?
If statistical English (mainly 3 and 5 above) is the reference, then the Chinese and the Indians can change English completely every few years with no significant efforts. If we exclude the Chinese and the Indians, what about Australian English? Why is it excluded? Nobody (e.g. dictionaries) explains anything about it, like they explain about UK and US English.
Related, but not the same, is this question - which differentiates between the "ultimate reference" of current English and the "ultimate reference" for the "new" English.