Answer: This is not the nature that we study as natural sciences like botany, zoology, etc.
Kabbalists investigate the relationship between all parts of nature, ours and that which is hidden from us, in its absolutely complete integral state. This is the subject of the study of Kabbalah.
The main thing is that we include in ourselves, our abilities to attain. And afterward, we begin to see that only as we improve our organs of perception, when we make them also infinite and perfect, it becomes possible to feel and understand nature and the Creator.
Spiritual laws are revealed in us to the extent that we can be in the quality of bestowal and love, in the quality above our own egotistic nature because we have developed the corresponding sensory organs.
Question: And before that, we can only hear that they exist?
Answer: We can read about this, but we do not understand what we are reading about.
Question: Do we have to believe in the existence of such laws?
Answer: There is no need to believe in anything. We must open our senses, raise them to the level of the quality of bestowal. Then, we will be able to explore the higher nature.
Nature is divided into two parts. One of them, the lowest or selfish nature of our world, works on the property of receiving. In this part we can comprehend all the laws of the still, vegetative, animate, and human nature functioning at the level of the material world.
But, in addition, there is the nature of the next, upper world, which works inversely like a mirror image, to bestow, not to receive.
From the Kabbalah Lesson in Russian 3/12/17