What is important is not so much how long you live as whether you live a meaningful life. This doesn’t mean accumulating money and fame, but being of service to your fellow human beings. It means helping others if you can, but even if you can’t do that, at least not harming them.
Concern yourselves more with the needs of others, with the needs of all humanity, and you'll have peace of mind. Selfishness creates a distance between us and other people, leading to suspicion and mistrust, ultimately resulting in loneliness. Think of others' well-being and you’ll be happy.
I believe that the very purpose of life is to be happy. From the very core of our being, we desire contentment. In my own limited experience I have found that the more we care for the happiness of others, the greater is our own sense of well-being. Cultivating a close, warmhearted feeling for others automatically puts the mind at ease. It is the principal source of success in life.