Heart's Desires

In Adage 15, Master Sheng Yen remarks, " In dealing with your heart's desire, ask yourself these questions: Do I need it, or do I want it? Can I acquire it? Should I acquire it?" This is similar to the first adage, only I think it's more related to reflecting on one's goals. In wanting something, I run the risk of suffering for it by engaging the sense of desire and grasping, especially when it isn't something I necessary need, or can live without. The tricky part about this adage, however, is to distinguish between "wants" and "needs".
  Needs are sometimes more easy to discern if they are directly related to survival. Food and clothing are examples of things that we supposedly "need", but there is a world of difference in terms of the kinds of food and clothing a person chooses for themselves. In fact, I can justify eating a luxurious dinner or flying in a private jet by boiling these down to "needs" (such as the need for food and transportation), but somehow these luxuries have ceased to be needs, and relate more to wants. I think that this also relates more to a mental attitude toward things around us rather than to the things themselves. I can eat a simple bowl of rice with a ravenous spirit of craving, or conversely, I can enjoy the bowl of rice with a quiet sense of contentment, neither clinging to the rice nor wanting to reject or ignore it. This middle way between craving and ignoring is a kind of gentle appreciation. It's not that I reject food altogether and live as an ascetic but I have a gratitude toward food for helping me to survive and sustaining me.
   The other point, "Can I acquire it? Should I acquire it?" is more interesting, because even if I accept responsibility for what I want, there are still questions related to ability (can I) and ethics (should I). Ability is an interesting one; many people want to extend themselves beyond what they are physically and mentally capable, in order to appear diligent, successful or "worthy" in others' eyes. But this "can" actually generates vexations and negative karma, because it doesn't respect one's current conditions. I am committing violence in forcing myself to attain a particular goal that isn't suited to my capacities. But even in cases where I have a strong constitution and ability to do things, there still remains the question of should I? An entrepreneur can invest millions of dollars in building a factory, but this factory might do a lot of damage to the environment. In this respect, ability does not necessarily lead to desirable ends for the world. Many people also internalize the attitude of "if it can be done, it should be done", and this too is a rather violent approach which valorizes outcomes simply because they are attainable or even challenging. But attainable and challenging are not necessarily valid reasons for pursuing a goal, since even polluting can come from a diligence in a certain direction. 
   Discernment is needed to understand whether one's goals are achievable or even desirable.

http://www.dharmadrum.org/content/about/about2.aspx?sn=46