Originally Posted by jungmark
Nope. An informed opinion/prediction is still an opinion until it is proven.
An opinion, pretty much by definition, can never be proven.
"Baseball is better than football." Prove it (or disprove it). Now, if someone said something like, "Baseball is a more popular sport than football in the US," that can easily be disproven by any number of metrics. But that's because there are FACTS involved. But, "Marlowe was a better writer than Shakespeare, " while being a fairly unpopular and fringe opinion (which, nonetheless is still held by some) cannot ever be proven or disproven. It's just up to the tastes of the individual reader.
A prediction is not synonymous with an opinion. A prediction, assuming the person has some background and foundation in the area being discussed, is envisioning what is a LIKELY outcome of events. This prediction is based on history, facts, trends, and an understanding of the area being discussed.
For instance, if Clayton Kershaw is pitching for the Dodgers against a rookie who had a 4.78 ERA and a 1.30 WHIP in the minors, and also had a less than 2-1 K/BB ratio, the PREDICTION that LA is going to win is a fairly solid one, based on given evidence. Does it mean that there is a 100% that the Dodgers will win? No. It just means that it's HIGHLY LIKELY given everything we know (both about the individuals involved and about baseball in general -- how games often revolve around the strength of the starting pitching, for instance).
No one ever said that a (well-arrived at) prediction is a fact. I just said that a prediction is not the same as an opinion.