It is not being happy in life, it is knowing the feeling in that moment is good - which makes us feel happy and our happiness quotient goes up in that moment. So - what is happiness quotient? It is an emotional equation, where the balance tells us whether to feel happiness or sadness. The equation goes something like this (limited for only that we consider as good for ourselves):
If you can convince yourself that the above equation works, you would know that feeling of happiness is not entirely out of your control. In many instances we bring down our happiness quotient by setting our expectations too high. This leads to a lower H.Q. and since bad feelings last longer, we become attached to this unhappy moment and carry on feeling sad for longer than the individual moment's outcome deserved.
Being in a state of anything changes from one state to another as water changes from being in the liquid state to solid state or gaseous state depending on conditions it is subjected to. We too change from being in a state of being happy (i.e. happiness) to being in the state of being sad - depending on the situations and conditions we are subjected to. Do we want to leave our happyness to the conditions we will never fully be in control of? It is by using the the power of conviction, ability to distance myself from the moment to look at my life in broader perspective and correctly evaluating the equation of happiness that I find my happyness.
Imagine how strong it is to be happy than be in the state of being happy. And I would any day be in the pursuit of happyness than momentary happiness.