The second Noble Truth is simple: the cause of suffering is desire. It doesn't matter 
how much wealth a man has because he desires more and no amount of pleasure or power really satisfies since he wants more. In short, we desire more of the same illusionary world ruled by egos craving attachment when, actually, there's nothing lasting and unconditional .
And so we suffer. German director Wim Wenders turned this notion on its head in his film Wings of Desire in which an invisible, immortal angel is doomed to listen to the thoughts of humans he can never interfere or physically interact with no matter how much he desires. It leads to intense suffering till, tired of only observing and never experiencing , he renounces immortality to become a participant in the world. The reason why both fulfillment of desire as well as its total denial lead to suffering is because some desires at least are essential to living - such as our desire for knowledge, truth or beauty for example.
They can be some of the most transformative agents for change and self-mastery in our lives. And it's the power of these desires - right-ordered and guided - which is one of the greatest triumphs of art, science and wisdom. The Buddha didn't witness disease, old age and death around him and say, "What the hell, that's the way it is and so be it." He desired to know what could be done about it and then went about doing it. When he got his illumination , he didn't say, "Okay, I'm done here." Instead , he went back because he desired others to know about it too.
Article by Mukul Sharma