The Yin-Yang symbol tells us that nothing lasts forever.  The universe and human kind are in a constant state of change.  We can see this in nature every year as the seasons turn.  Things will sprout, flourish, wither and then die.  The same thing happens in human affairs.  Good times will be followed by bad times.  Progress will be followed by regress.  Remember that the Tao Te Ching tells us that the ugly and the beautiful are both natural because they give measure to each other.    If you are enjoying any current state of affairs, beware that within the current state is the seed of change (those little dots in the symbol), which sooner or later will take root and give rise to change.  Understanding and accepting the constant cycles of change talked about in the Tao and represented in the Yin-Yang symbol is an important step to succeeding in regulating your emotional mind and in creating a strong and steady spirit.  If your wisdom mind can understand and accept the cycles of change, then your emotional mind can remain calm and your spirit remain steady as you view and experience change.  It’s not easy, particularly not easy if you are attached to the things of the human world.