If you're trying to win an argument, you need facts.
If you're trying to win a person over, you need far more than that.
Even though we like to think we make our decisions based on facts, the final deciding factor is very often based on an emotion.
A person can have all the information pointing towards a certain action, but still not want to do it.
For example, you can present scientific evidence to a smoker about how harmful smoking is, show them statistics of diseases and deaths caused by smoking, even impose fines and penalties on them.
But they're not going to stop smoking.
Some even argue back, that their uncle or someone they know lived to nearly a hundred years old despite being a smoker, that they have always been healthy and have no illnesses, that they can afford to pay if they have to.
Mere facts aren't going to change their behaviour.
And facts aren't going to sustain them through the difficulties they'll be going through should they change their behaviour.
In the case of smokers, that may include the withdrawal symptoms, the perceived "loss of face" for always previously refusing to quit, the loss of time spent with their smoke buddies, etc.
To truly change their behaviour, something has to strike them emotionally.
It can be nearly any emotion:
Fear of getting sick after they see a beloved relative get ill, or of dying after getting sick themselves.
Anger at wanting to prove their friends wrong, after being told that they will always be a slave to tobacco.
Love for their newborn child, with a desire for him/her to grow up in a healthier smoke-free environment.
That emotion is not only a stronger force for change, it is a greater sustaining force for the difficulties they'll experience while they are changing.
And you can be sure that manipulative people and groups know this well. Why do you think they keep bringing up emotional arguments, instead of factual ones?
So, if you really want to make positive change for yourself and/or those around you, appealing to emotions, backed up by some solid facts (because some of us really do want / need them) is the strongest way to go.
It isn't a one-or-the-other thing, it's a co-operative thing. Both work best in tandem.
Being Opinionated Is Not a Bad Thing. IF You Know How To Be.
It's okay to be opinionated.
IF you have good research and listening skills, know how to express your arguments tactfully, succinctly, and elegantly, and know when to keep your peace.
Having research skills, and putting them to use, reinforces your opinions with (at least some) facts.
Listening skills helps you to make sense of what other people are saying and not saying.
Being able to express your arguments well not only keeps you from turning your argument into an unnecessarily long rant, it also helps others keep track of what you're saying.
You may even convince a few.
Finally, knowing when to yield ground, when not to belabour dead ends, and when to just let things slide, keeps you from becoming too uptight, and keeps your relationships intact.
Please don't become that contrary, obnoxious person who butts into everyone's conversations and doesn't know when to shut up or concede.
Sometimes, keeping it light is the smarter way to go.
But hey, that's just my opinion.