Does anyone else see the irony in arguing over whether arguing changes other people's opinions?
Informed opinions should change as further information is received.
It is my opinion that refusing to alter or change completely your viewpoint, after being presented with facts to the contrary is the acme of stupidity.
Maybe this node should have considered whether rhetoric can ever change opinion, as it seems many public debates these days are about rhetoric, soundbites and spin as opposed to a clear presentation of the facts.
It seems to me that issues such as abortion, gun control in the US, tax reform and the environment are dominated by groups who predominently use rhetoric to try and persuade others. They mix in just enough fact so that their arguments sound authoritative, but for the most part they are simply expertly crafted speeches given by skilled orators. It also helps that most of the time the speeches are directed at followers of their cause, and the aim isn't to persuade people to change their minds, but to reaffirm their beliefs (and therefore donate more money to the cause).
The line between fact and opinion has been blurred to such an extent that it can be difficult to spot especially when it is difficult to judge the veracity of facts presented.