Facts and Opinions

I realised that a lot of my thinking and posts and justifications I have tried to write for this blog it comes down to trying to justify my opinions or point out where someone else have their facts wrong. Perhaps that is a bit harsh on myself, I've usually ended up trying to say something along the lines of 'be more open minded'. Then of course there's the great phrase 'if you open your mind too much your brain will fall out'. i.e. you can't be fully open to every idea and still make critical conclusions.
Anyway I'm getting sidetracked, the nature of Facts and Opinions as it appears to me:

No opinion is 100% defensible. For any opinion you invent can be found an example or an argument that shows the flaw. Pick any opinion whatsoever and you can find a flaw. Conversely pick any opinion whatsoever and you can find merit in that too. Let's try some obviously flawed statements and find the merit:
"Black is the only colour a person should wear." Well it would make shopping and getting ready in the morning MUCH easier.
"Since a mature rainforest is actually carbon neutral whereas farms are carbon negative, the question of deforestation is actually one of what we do with the trees we cut down". If you could make this work sustainably and bury all the wood for less than the carbon cost of transport you should be able to cut down on world hunger.
"The world was a better place for humans in the stone age." Clear gender roles, unambiguous deity requirements, ample scope for innovation, plenty of opportunity for free enterpise etc.
"The Amiga is a better computing platform than Windows 8". Faster boot time, lower hardware cost, quicker to learn, simple programming model etc.
From this I take that no matter how ludicrous anyone else's opinions may seem there is going to be something they can say to defend it. Likewise no matter what opinions I hold are going to be equally subject to criticism.

No fact (ignoring Mathematics but I'll come back to that) can be 100% true. This is pretty much a ground rule of science, something is only a valid theory if it is possible to be disproved. The mainstay example of this is evolution, which has been done to death elsewhere but all of science is (almost by definition) filled with examples of theories that could be wrong but all available evidence indicates perhaps they are on the right track.
As for Mathematics, we can be sure things are 100% true there because we make up all the rules, so for most of life that is not applicable (where we can make up some of the rules but not all of them).

Where does this leave us? In much of life, much conversation, debate and policy is determined based upon a mixture of fact and opinion. Laws and fortunes are decided on the outcome of which is better: the Iphone or Android phone of the day, Windows or Linux, Conservative or Labour, Oranges have a good or bad harvest this year etc. Deciding which is right between a number of competing options represents a good chunk of what humans do. Any of the above examples might be found to have an outcome (Iphone sells more) but is it really better? The answer is always going to be subjective and insubstantial.

So what is the point of all this? To try and change the way we look at debates and discussions and human interaction in general. If both parties go into a conversation not just with the acceptance that they themselves might be wrong (which would be a big improvement on any number of internet arguments) but with the assertion that they almost certainly are wrong from the other person's perspective and their role in the discussion is to try and find the pros and cons of not just both sides, but of every side.
So there's my opinion on opinion. I put it out there for you to critique and show me where I am wrong, (because by my own argument I am, so the question is: where?).