This is an interesting question, sounds simple but it involves different aspects, is one of those questions that the answer depends on your mood.
Well, first of all, I think life is just life, not fair or unfair, it just is, what's fair or not are persons, actions, consequences. I believe in karma, it's pretty clear that every action has a reaction and that reaction can be fair or unfair depending on what you did to cause it.
For me life has been a balance between both, there are periods of time where all seems really unfair, as if life were using you as punching bag and all you want to see is the end of its unfairness, then the scale changes and life picks another one to be its punching bag and you start to see the sweet side of things.
In order to clearly see and feel the fair things life throws at you there has to be a comparison point, that's why going through unfair times is necessary.
Some say that your attitude during unfair moments is the key that determines if you are strong enough to endure it or not, there's some truth to that but... well, it's unfair that we can't have a good attitude when we need it, sometimes it's hard to smile positively at unfairness, but if we focus on the fact that things change and we won't be stuck facing the unfair forever it can give us some hope.
And when we're dealing with what's fair, being real that suddenly things could turn unfair helps us to keep our feet on the ground.
I used to believe that life is fair if you're fair, but I've seen many fair persons complaining that something's not fair, even if you do nothing to deserve bad things, the unfair will come, it's inevitable but it's all part of balance, every force, every concept needs its opposite to exist.
I've complained about salaries not being fair, but complaining I won't change how things are, what I can do is work harder to get a second income, but I would still complain about life being unfair because, why do I have to work harder to have less than half of what others have?
Then there's the other side of the coin, other persons say it's unfair that they have to work even harder to get what I have, if the perspective changes then I am on the fair side...
It's not easy to define what's fair and what's not, there's always going to be different perspectives that will make you go from one side to another without us having any control over it.
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