What does this have to do with philanthropy? Surprisingly, everything. Philanthropy—in terms of physics—is the transfer of energy from one system to another, from one with a surfeit of power to one with a deficit.

When we send a planeload of food to a devastated area, the core biological purpose of our assistance is to transfer the energy in that food to the food eaters, whose bodies transform it into prana—life energy—which they can use to heal, to bury their dead, and to remake their lives, their homes, and their communities.

But where does food come from? There’s no food without rain. The Indian Bhagavad Gita, one of the seminal texts of yoga, explains the cycle of sacrifice thusly: From food comes forth living beings, and from rain food is produced; from sacrifice arises rain, and sacrifice is born of work. Thus rain is sacrificed to food, and food to the digestive fire in our stomach. From the energy we get from food, we’re able to perform our work and to reap the treasures of the earth.

When a part of these treasures is offered back, the gods become pleased and send their blessings in the form of rain. Thus the circle of sacrifice is completed. This is the ancient paradigm.

Note the vital importance of wealth. The earning and accumulation of wealth is not regarded with disdain. Indeed, it’s just the opposite. Because energy cannot be created, sacrifice or philanthropy demands an existing pool of resources that can be “sacrificed” to those in need. Thus, in the ancient Jewish tradition, sacrifices were made from domestic animals, not wild ones, because wild animals do not belong to anyone.

In fact, one might say that the ultimate purpose of rain, food, and work is the creation of wealth and value—but with one essential caveat: that this money be used righteously and unselfishly, and that a portion of it be returned to its source and plowed back into the community. Thus, the cycle of sacrifice is completed, and a new one can begin. The study of this subject over the years has altered my own attitude toward money. I’d often been told that money was “the root of all evil.” But the original Latin adage reads Radix malorum est cupiditas—“Greed is the root of all evil,” not money.

What is greed? We often envision it as a rapacious desire for more. But just as often, greed wears a more pedestrian face and takes the form of simply not giving.

Today, as we cast about for better ways to make our giving count, ways “that integrate social, ethical, and environmental principles,” as the author and environmentalist Paul Hawken puts it, we could do worse than to reexamine this old model, or cycle of life.

However we view it, the Circle of Sacrifice positions philanthropy within a larger context. Philanthropy here is more than a “random act of kindness.” It is an integral, regular, regenerative link in the circle of community and life. According to this ancient viewpoint, without giving, without philanthropy, the wheel of life would stop.

Of course, you may be wondering how relevant this perspective can be today when many of us don’t believe in a quid pro quo between the pleasing of supernatural powers and the fall of life-giving rain. But the gods of antiquity were closely identified with the classical elements: Fire, Air, Earth, and Water, and can be viewed just as truly as the forces of nature.

Given the many streams that come together in philanthropy—and the present state of our biosphere—a broad and integrated approach like this one feels overdue.