Happiness and freedom begin with a clear understanding of one principle: Some things are within our control, and some things are not. It is only after you have faced up to this fundamental rule and learned to distinguish between what you can and can't control that inner tranquility and outer effectiveness become possible.
EpictetusWhen any person treats you ill or speaks ill of you, remember that he does this or says this because he thinks it is his duty. It is not possible, then, for him to follow that which seems right to you, but that which seems right to himself.
Epictetus