Emotions flow like water. They are fluid. Not stable. Often we can't predict their direction. In such a case, understanding human emotions cannot be called a science. It can't fix into a mathematical formula. It is neither science, nor maths - because science, and maths are exact sciences. Their accuracy is measured through formulae. Emotions can't be measured. Because their mastery is totally rare. However, if emotions were mastered, their volatility in our life could be controlled, we would become their masters. Happiness then would no more be a subjective study, it would become a perfect science. At this point, happiness is maths.
Life can be lived either through emotional turbulence or emotional stability. When there is turbulence, we feel happy and sad very fast. It seems everything is affecting our emotional scale one way or the other. We have become a servant of our emotions. They rule over us. The opposite is the case with emotional stability. A stable person gets neither excited too fast, nor sad too fast. It appears as if he is a mere observer to his own life, it appears he is not an engrossed participant. This stable mental state is the path towards happiness. It's contentment is internal, it is quite unaffected by its surroundings. This is the moment when happiness does not play with you, but you play with happiness. The choice is yours. Happiness is married to you. It's in your hands. You have converted happiness into maths.
Happiness is manifested in contentment. This means you are happy with the present. You live in the joy of the present. The tomorrow holds no worries, tensions, or ambitions for you. Because there is no tomorrow. You do not seek a brighter future. You only have learnt to enjoy the present. Happiness does not have a future tense, it now only has a present tense. Now, happiness is maths.