Pursuit of happyness

Once I started to work after my masters life had become a routine for me. Every day leave to work around 7:30 or 8 am and come back at 7PM. Since I arrived at Dallas for my studies I was always worried about some thing or the other and was thinking some day all my worries will be gone. When I was in Bangalore, I was worried will I get admission to University , when I got it I was worried will I get Visa, once I came to US I was worried about what subjects to take and then a job, after that better job it had no end.
One day on my way to office I was waiting for bus at the bus stop. As I stood there I watched a young guy who held a walking stick walk out of the bus, he was little bit mentally challenged too. He came up to me with such a big smile, he took my office ID card looked at my photo and although had difficulties in speaking he said Hello to me and asked me all details about what I do and where I work. Then he patted me on the back with so much of josh, and wished me all the best and left. That day when I went back home I was just thinking, have I forgotten some thing in life? Yes I forgot to live life without worries. Here I was in this world with all the reason to be happy and he did not even half the reasons as I had to be happy but still I was not so happy and he was. The biggest thing we need to learn in life is to be happy amongst all worries.