Kabbalah: That which is received. That which cannot be known through science or intellectual pursuit alone. An inner knowledge that has been passed down from sage to student from the earliest of times. A discipline that awakens awareness of the essence of things.

We enter this world and our senses meet its outer crust. We touch the earth with our feet, water and wind splash against our skin, we recoil from the bite of fire. We hear sounds and rhythms. We see shapes and colors. Soon we begin to measure, to weigh and describe with precision. As scientists, we record the behaviors of chemicals, plants, animals and human beings. We video-tape them, observe them under a microscope, create mathematical models of them, fill a supercomputer with data about them. From our observations we learn to harness our environment with inventions and contraptions, and then pat ourselves on the back and say, Yes, we got it right.

But we ourselves, our consciousness that is examining this world, we reside on a deeper layer. That is why we cannot help but ask, What about the thing itself? That which is there before we measured it? What is matter, energy, time, space — and how do they come to be?

To explain our world without examining this inner depth is as shallow as explaining the workings of a computer by describing the images viewed on its monitor. If we see a ball moving up and down on the screen, would we say that it is rebounding against the bottom of the screen? Do the gadgets on your scroll bar really exert some force on the page inside the window? Does the menu bar really have drop-down menus hidden behind it?

The author of a user-friendly software environment has followed consistent rules so that we can work comfortably within it. If it is a game of any complexity, he had to determine and follow a very large set of rules. But a description of those rules is not a valid explanation of how it works. For that, we need to read his code, examine the hardware, and—most importantly—look through his original concept paper. We need to see it the way its author sees it, as it evolves step by step from a concept in his mind through the code that he writes, to the glowing phosphor pixels on the screen.

The code behind reality, the concept that breathes life into the equations and makes them real. Men and women have sacrificed their food, their comfort, traveled great distances and paid with their very lives to come to know these things. There is not a culture in the world that does not have its teachings to describe them. In Jewish teaching, they are described in the Kabbalah.

According to tradition, the truths of the Kabbalah were known to Adam. What his mind held, no mind since has been able to conceive. Yet he was able to transmit a glimmer of this knowledge to a few of the great souls that descended from him, such as Hanoch and Methuselah. They were the grand masters who taught Noah, who in turn taught his own students, including Abraham. Abraham studied in the academy of Noah's son, Shem, and sent his son Isaac to study there after him. Isaac in turn sent his son Jacob to study with Shem and with Shem's great-grandson, Eber.

Adam, Noah, Abraham—these were fathers of all humankind. That is why you will find inklings of the truths they taught wherever human culture has reached.

Nevertheless, the essential source for the Kabbalah is not Adam or Noah or even Abraham. It is the event at Mount Sinai, where the primal essence of the cosmos was laid bare for an entire nation to see. It was an experience that left an indelible mark on the Jewish psyche, molding all our thought and behavior ever since.

At Sinai, inner wisdom became no longer a matter of intuition or private revelation. It was now a fact that had entered our world and became part of history and the experience of common mortals.

That is why Kabbalah cannot be called a philosophy. A philosophy is the product of human minds, something that any other human mind can come play with, squeezing and stretching it according to the dictates of his own intellect and intuition. But Kabbalah means, that which is received. Received not just from a teacher, but from Sinai. Once a student has mastered the path of this received knowledge, he or she may find ways to extend it further, as a tree branches out from its trunk. But it will always be an organic growth, never touching the essential life and form of that knowledge. The branches and twigs and leaves will go just where they should for such a tree—never will a Maple become an Oak, never will a student reveal a secret that was not hidden in his teacher's words.