Calm, joy and happiness are states that arise on their own due to the combination of the conditions that are present. If you are doing something that you enjoy the conditions that support happiness may be present and therefore you would probably due this again. If you get caught in the rain without an umbrella the conditions present may create the arising of irritation. You might choose to carry an umbrella.
If you are sitting in meditation or just looking out the window with your feet up on the desk the echo of past conditions has left impressions within you. A fun practice is to check in and see if there is any lingering gladness in your mind/body. Without trying to create or reach out in memory just sense the feeling of gladness and see if it is present. Like different colored specks of dust floating in the air various wisps of feelings linger within. See if any gladness may be floating by. If you sense it merely allow it to be present without grasping. You might try to support it as you would hold a baby chick. Or gently blow on it as you would turning glowing kindling into flame.
Another place to look for gladness is the lack of any present hindrances to gladness. The hindrances are wanting either more or less of something, having ill will towards anyone or anything, restlessness, boredom and having doubt about anything. Check in and see if there is a lack of some hindrance that is often present. The lack of a hindrance allows for some gladness in this moment. Return to gentle support or gentle blowing of this gladness too.
As small moments of gladness accumulate you start to spontaneously notice them arising and being present more often. In a short time you may discover that the nudging of Spiritual Gravity is pulling you through gladness and inward to true happiness.
Spiritual Gravity 