Kundalini.Tantra.by.Satyananda.Saraswati

Therefore, in my opinion, only those who are adepts in yoga qualify for vama marga.
This path is not to be used indiscriminately as a pretext for self-indulgence. It is meant
for mature and serious minded householder sadhakas, who are evolved, who have been
practising sadhana to awaken the energy potential and to attain samadhi. They must
utilize this path as a vehicle of awakening, otherwise it becomes a path of downfall.
Section 2 - THE CHAKRAS
Chapter 1
Introduction to the Chakras
The subject of chakras is not going to be an easy one. Many scientists and
philosophers are confronted with a great difficulty when it comes to accepting and
explaining the existence of the chakras. They do not know whether the chakras are to be
found in the physical body or in the subtle body. If they exist in the physical body, where
are they? And of course the subtle body is not the matter of modern anatomical science.
In the past, doctors and scientists used to ask me: 'We have witnessed many
operations, why have we never seen the chakras?' At the time, the only reply I could give
them was, 'Can you show me the sound waves in a transistor radio? I have opened up
radios but I have never found the BBC there.' This answered their questions, but it didn't
really satisfy them. Scientists want a scientific explanation, and for this, new areas of
research are being developed.
An eminent Japanese scientist, Dr. Hiroshi Motoyama, has invented sensitive
machines for measuring the vital energy of the body. One apparatus measures the
functioning of the nadis and their corresponding body organs, and this machine is now
being used in some Japanese hospitals to diagnose disease tendencies before they actually
manifest. Another invention is 'the chakra machine', which records the impulses that
emanate from the psychic centers in the spinal cord. On this machine it is possible to
register definite impulses from these areas in individuals who have been practising yoga
for many years, and who have awakened their psychic faculties. For example, when a
subject practises pranayama with kumbhaka and maha bandha - contraction of the
perineum, abdomen and thyroid, the machine registers changes in the impulses emanating
from the psychic centers. This research shows that energy is definitely activated by the
yoga practices. However, we still have a lot of research to do in order to provide more
scientific explanations.
At the same time, there are quite a lot of different interpretations on the science of
chakras. Of course the differences are not that great, but they are there. The thinkers of
theosophical movements and their predecessors have their own interpretations of the
chakras, their location points, colors, etc. The Rosicrucians and others may say something
completely different and the tantric texts may present entirely different concepts.