What is Kabbalah?

Although its origins are rooted in deep antiquity, from the time of ancient Babylon, the science of Kabbalah has remained virtually hidden from humanity since it appeared more than four thousand years ago.This very concealment has sustained Kabbalah's undying allure. Renowned scientists and philosophers of many countries, such as Newton, Leibniz, and Pico della Mirandola, have investigated and tried to understand the science of Kabbalah. However, to this very day only a few know what Kabbalah really is.

The science of Kabbalah does not speak about our world, and therefore its essence escapes people. It is impossible to comprehend the invisible, the imperceptible, and that which has not been experienced. For thousands of years, humanity was offered a wide variety of things under the name "Kabbalah": spells, curses, and even miracles, all except for the science of Kabbalah itself. For over four thousand years, common understanding of the science of Kabbalah has been cluttered with misconceptions and misinterpretations. Therefore, first and foremost, the science of Kabbalah needs to be made clear. Kabbalist Yehuda Ashlag defines Kabbalah in the following manner in his article The Essence of the Wisdom of Kabbalah :
This wisdom is no more and no less than a sequence of roots, which hang down by way of cause and effect, in fixed, determined rules, weaving into a single, exalted goal described as "the revelation of His Godliness to His creatures in this world".
Scientific definitions may be complicated and cumbersome. Let's try to examine what is being said here.
There exists the upper force or the Creator, and governing forces descend from this Upper Force into our world. We do not know how many forces there are, but this is actually unimportant. We exist here in our world. We are created by some upper force that we call "the Creator". We are familiar with various forces in our world, such as gravity, electromagnetism and the power of thought. However, there are forces of a higher order that act while remaining hidden from us.
We call the ultimate, comprehensive force "the Creator". The Creator is the sum of all of the world's forces and the highest level in the line of the governing forces.
This upper force gave birth to the upper worlds. There are five worlds in total. The so called Machsom - a barrier that separates the upper worlds and our world - follows them. From the Upper Force - the Creator, also known as "the world of Infinity" - the forces descend through all the worlds, giving birth to our world and human beings.
The science of Kabbalah does not study our world and humans in it, as traditional sciences do. Kabbalah investigates everything that exists beyond the Machsom .
Kabbalist Yehuda Ashlag says that "this wisdom is no more and no less than a sequence of roots, which hang down by way of cause and effect, in fixed, determined rules..." There is nothing other than forces descending from above in accordance with precise laws. Moreover, these laws as Ashlag writes, are fixed, absolute and omnipresent. Ultimately, they are all directed so that one can reveal the ultimate governing force of nature while being in our world.
Until a person fully reveals this force, until one knows all the worlds one has to climb, obeying the same laws as the descending forces, and until one reaches the world of Infinity, such a person will not leave this world. What does "will not leave" mean? This person will continuously be reborn into our world, evolving from one life to the next until reaching the state where the desire to attain the higher force emerges.