Joy, rather than happiness, is the goal of life, for joy is the emotion which accompanies our fulfilling our natures as human beings. It is based on the experience of one's identity as a being of worth and dignity.
Joy is the effect which comes when we use our powers.
There is a curiously sharp sense of joy - or perhaps better expressed, a sense of mild ecstasy - that comes when you find the particular form required by your creation.
Now, I believe in life, and I believe in the joy of human existence, but these things cannot be experienced except as we also face the despair, also face the anxiety that every human being has to face if he lives with any creativity at all.
The insight is born with anxiety, guilt and the joy and gratification that is inseparable from the actualizing of a new idea or vision.