“All things are impermanent”, is a Buddhist saying which I find very true personally. You will find sunshine after rain, happiness after depression. But also rain after sunshine and depression after happiness. The manically depressed among us seem to be addicted to this loop and feel they cannot escape. I guess we all have this feeling of being under the control of our emotions some time. The Buddhist saying helps to see the bigger picture during moments of sadness. It will pass, as will happiness. So live now, now is all we have. Emotions are like sine waves, some have a long period but a small amplitude. Others are the opposite. The sum of all these emotional sine waves over the span of a lifetime makes me think of a fourier transform. Do we have any control over this transform? Can we transform ourselves?