The ancient Chinese yin-yang symbol represents the balance of yin (peacefulness, serenity, acceptance, rest, rejuvenation, roots, tradition) with yang (activity, strength, striving, movement, change, wings, invention, progress). A meaningful and joyful life is to be found in balance.

In the midst of movement and chaos,
keep stillness inside of you.
- Deepak Chopra

Manage the remarkable balance between acting
from your heart and close to your gifts
with completing the obligations
that your labor and tasks require of you.
Leverage opportunity AND seize joy.
- Mary Anne Radmacher

To go beyond is as wrong as to fall short.
- Confucius

Be aware of wonder.
Live a balanced life -
learn some and think some
and draw and paint
and sing and dance
and play and work every day some.
- Robert Fulghum

Maintain a balance between skepticism and faith.
Maintain a beginner mind. Be open to possibility.
Don't give in to skepticism,
but don't give in to fantasy either.
- Jonathan Lockwood Huie

Further reading: Go With the Flow - Six Ways to Live a Happier Life

Finding Balance in Life

Balance Work and Play