Many questions ask if something is possible (or where can I do x in y). Often the answer is hard to find out and in a good part of these cases the answer might be "no, that is impossible, you can not do this for a reason."
However I feel that we are (recently) too easy on answering that something is not possible. IMHO if I do not find def info on the net, I might leave a comment but I leave the question open.
This I do because it will be considered open and seen by other users who might know/google more/better than myself. Having a question answered, discourages other users from looking at it and it will go down the drain into question nirvana without a proper answer.
For example I waited three months to answer that SanXingDui art question even though I had that suspicion for all the time, I was waiting to find better sources. In that recently popular question on strike websites in France many people commented or answered that such a site would not exist only for one to be found within a day.
In a more scientific wording, I feel we should reduce our number of potentially false negatives.
Now this is my opinion and please answer and comment and vote wildly on here about what you feel about this topic.
Thanks to @Berwyn for pointing to these two related meta SO and meta SE posts. I still think it is useful to have such a separate discussion for travel though as in many cases it is not as easy to say something is impossible (and I don't accept "half an hour of googling around did not give me results" as impossible) in travel as it might be for programming. Also these posts discuss if it is OK to post "impossible" as an answer whereas I would like to discuss if we are too easy/quick in doing so.