Why we are sad?

Sad: I feel everyone can be sad from time to time and this is a normal phenomenon. If you feel this is long lasting or happens frequently then you may need to evaluate your life to see what is causing your sadness. If you cannot determine this, then you may need to go to your doctors to receive a comprehensive evaluation.

We are blessed: to have the capacity to feel an array of emotions. Sadness provides us with an emotional reaction to things like grieving, loss, difficult experiences, disappointments, etc. Because we have the ability to feel sad, or angry, or scared - it makes it all the more special when we feel joy or happiness (as we now have something to contrast it to).