Reply #2: One of the purposes of science is to test out "common sense" knowledge

[salvorhardin]

Because frequently, what's common sense is wrong and even if proven right, it's always better to make decisions based on facts rather than opinion. For instance, with this particular study, assuming it was a good study (I haven't read it), we now know that there is hard evidence to support public smoking bans. This can be used by citizens and legislators to get public smoking bans passed in states and municipalities where such laws might not have made it onto the books before.