Something happens and we break out of our old thought pattern, have a new thought!
We rejoice if it is something good and different, if our mind has moved on to something positive, beautiful, exciting.
We are sad if it causes us sorrow, pain or confusion.
These thoughts of ours, they never stop. They arise, are here for a while and then are gone.
If we can see them just as thoughts that come and go, we can have a little more peace or equanimity in this life.