“The human energetic system is very complex and it is even harder to understand the mind, the structure, the limitations and possibilities, the relationship with the body and vice versa.
On the other hand, we can easily say to someone that there are seven Cakra, that they are like this or that, that there are found here or there in the body etc in all simplicity. But we must be aware if we do that we haven’t really said anything, and the person will not be any the wiser.
The risk of confusion is even greater when we try to show the model of the Cakra scientifically, or to give spiritual characteristics some sort of scientific basis. Some try to do this, by linking Mūladhāra with the kidneys or the sacral plexus, or Viśuddhi with the thyroid, etc.
Have no illusions: the model of the Nāḍī and Cakra can never help to explain physiological processes which accompany Yoga practice, and that is as it should be. The wish to mix a system like that of the Cakra with physiological science only serves to increase confusion on the subject.
Those who still persist in trying to establish these impossible connections simply risk making fools of themselves. To this day, every attempt to establish correspondences between the two systems are shown as superficial, as of doubtful estimation, and falsely simplified science.
More seriously, they take no account of the real significance of this ancient system, and don’t respect it, don’t do it justice and place attention on other priorities than Yoga does. In proceeding in this way, they cut themselves off from any possibility of understanding why these concepts still have a validity today.”