If we examine our life we will discover that most of our time and energy is devoted to activities, such as seeking material and emotional security, enjoying sensory pleasures, or establishing a good reputation.
Although these things can make us happy for a short time, they are not able to provide the deep lasting contentment that we long for. Sooner or later our happiness turns into dissatisfaction, and we find ourselves engaged in the pursuit of more worldly pleasures.
Directly or indirectly, worldly pleasures cause us mental and physical suffering by stimulating attachment, jealousy, and frustration. Moreover, seeking to fulfil our own desires often bring us into conflict with others.
If true fulfilment cannot be found in worldly pleasures, then where can it be found? Happiness is a state of mind, therefore the real source of happiness lies in the mind, not in external circumstances.
If our mind is pure and peaceful we will be happy, regardless of our external conditions, but if it is impure and un-peaceful, we will never find happiness, no matter how much we try to change our external conditions.
The method to make our mind pure and peaceful is to train in meditation. If we train our mind to become peaceful we will be happy all the time, even in the most adverse conditions. But if our mind is not peaceful, even if we have the most pleasant external conditions we will not be happy. Therefore it is important to train our mind through meditation.