The seven rays ..... represent the outflowing energy
from the seven centres of force in the Logos; they represent
seven forces, so to speak, which must enter into everything
in the universe. No object can exist without the presence
of each of these seven forces.

"...our brother, Mr. T. Subba Row, the most learned occultist
in India at this time, a disciple of the Himalayan
Hierophants..."
(H.P. Blavatsky 1883) [1]
When the seven rays we have spoken of proceed from
the Logos, they are separate, and subsequently co-mingle
in the formation of all beings. When an individual begins
his course of evolution, these rays are equally balanced
in him, none preponderating more than another. In the
course of time the man's actions, his karma, cause him
to come particularly under the influence of one or another
of the rays. Upon this ray he must make his further
progress, till he has succeeded in merging his life
in the life of the Logos - the grand fountain-head of
light and power.
When this mergence takes place, the man does not
suffer loss of individuality; rather he enjoys an almost
infinite extension of individuality. Each of the seven
classes of Logoi has its own peculiar consciousness,
and knows that this is so; that is to say, each Logos
recognises its own light; but each Logos also participates
in the life of all the other classes of Logoi; that
is to say, the peculiar quality of their life is represented
in it also; so that an individuality, in merging in
a particular Logos, is not cut off from the consciousness
of the other Logoi, but shares in, and experiences,
their consciousness also.
[1] http://ourworld.compuserve.com/homepages/dp5/subba.htm
N.B. "The deep occult knowledge which the late
T. Subba Row possessed is attested to again and again
by H.P.B. She has considered him as having more occult
knowledge than herself, and the first draft of The Secret
Doctrine was sent to him by her for correction and revision."
(from Esoteric Writings by T. Subba Row)
Extracted from a discussion with Mr. Subba Row at
the Adyar Library, held on 1st December, 1888, which
appears in a more complete form at:
http://www.katinkahesselink.net/sr_india.htm