Two Kinds of Energy
Excerpted from Subtle Energy: Awakening to the Unseen Forces in Our Lives by William Collinge, Ph.D., Warner Books, Inc., 1998  

To understand how to cultivate vital energy we need to look more deeply at the nature of it. According to taoist energy theory, we have both congenital chi and acquired chi. Congenital chi translates roughly as "essence" or "sexual essence." Our congenital chi underlies our basic constitutional strength and is determined by the energy of our parents, our in-utero nutrition, planetary influences at conception, and possibly past-life phenomena.  

It cannot be replaced, but is gradually spent over a lifetime. It can be conserved by healthy lifestyle, meditation, and certain sexual practices; but it becomes depleted through overwork, unhealthy living habits, and sexual excess. Just as a battery gradually is depleted through use, and a generator can restore some power temporarily, as the battery ages it eventually becomes unable to hold any charge at all.  

Walter has an abundance of congenital chi, but he augments it with acquired chi, that which we gain from food, energetic herbs, and air. Acquired chi helps to conserve our congenital chi, and the two work together synergistically for longevity and personal power.  

The marriage of these two kinds of energy explains the differences in people's energetic resources. All of us are capable of raising the level of our vital energy with use of acquired chi and by conserving our congenital chi. In the remainder of this chapter I'll explain how we can care for our vital energy through our patterns of activity and rest, food, energetic herbs, energy practices, and sexual practices.