Happiness is not a datum All we human beings are chasing happiness in entire life. Every individual makes a series of choices accessing to the destination of joviality. But what the happiness really is? It is hard to say clearly. I think there are some reasons as follow. Firstly, happiness is a feeling without rational thinking, therefore, it is always not has a criteria to weight it like a slab of beef. Secondly, two persons ,living in different situation and expiring diversity affairs, would hold two views about one case. For example, a vehicle of Aston Martin would not got a highly evaluation from a rich man, while treasured by common citizen earning little salary. Thirdly, age might a significant reason about whether a man feel happy or not. When I was a child, I had a dream that running a retail shop one day , from which I could eat any snack I am loving in. But it was not a dream anymore when I grown up, cause nosh would not provide sufficient to a adult. Despite defining happiness is not a easy task, here are some factors where the feeling of it stem from. Initially, heath, a basic factor we always ignore when we living without sick, is the primary element. Actually, people could not imagine how harsh a life could be before he or she suffering a illness. My best friend used to an ambitious talent until he attacked by a chronic stomach sick. The sorrow experience pushed him away from being a superstar in career and let him rethinking his lifestyle. Then, we obtain happiness from material conditions. For instance, living under the stress of less money surely may harmful to people. But material conditions is not equal to having numerous wealth like a millionaire. I agree with the mind of “less is more”, a sentence a Swedish friend told me. When I travelled to Scandinavia last winter, the Swedish photographer told me that I should not eager to buy a new camera just because that I do not need to focus on equipment, and spirit is more important when taking a photo of Northern Light. Lastly, achievements in specific field makes people happy in heart. This factor is linking to human’s natural demand that to be respect and highly evaluated by others. In conclusion, happiness is a private feeling rather than a datum calculated by a formula.