To be constantly without desire is the way to have a vision of the mystery of heaven and earth. For constantly to have desire is the means by which their limitations are seen.
The Tao doesn't take sides; it gives birth to both good and evil. The Master doesn't take sides; she welcomes both saints and sinners. The Tao is like a bellows: it is empty yet infinitely capable. The more you use it, the more it produces; the more you talk of it, the less you understand. Hold on to the center.