ental activity on the
astral plane. It is more than a powerful disturbance in the body of the
human aura, although this is the place of its embodiment or birth in the
objective world. It is formed in the following manner: A person
manifests a strong desire, feeling or idea, which is naturally filled
with the dynamic force of his will. This sets up a series of strong
vibrations in the body of the aura, which gradually resolve themselves
into a strong whirling centre of thought-force involved in a mass of
strongly cohesive auric substance, and strongly charged with the power
of the prana of the person.

In some cases these thought forms survive in the auric body for some
little time, and then gradually fade away. In other cases they survive
and maintain an almost independent existence for some time, and exert a
strong influence upon other persons coming in the presence of the
person. Again, these thought forms may be so strongly charged with
prana, and so imbued with the mental force of the person, that they will
actually be thrown off and away from the aura itself, and travel in
space until they exhaust their initial energy--in the meantime exerting
an influence upon the psychic aura of other persons.

A thought-form is more than merely a strongly manifested thought--it
really is such a thought, but surrounded by a body of ethereal
substance, charged with prana, and even carrying with it the vibration
of the life energy of its creator. It is a child of the mind of its
creator, and acquires a portion of his life-essence, so to speak, which
abides with it for a longer or shorter time after its birth. In extreme
instances it becomes practically a semi-living elemental force, of
necessarily comparatively short life.

To those who find it difficult to understand how a thought-form can
persist after separation from the presence of the thinker, I would say
that the phenomena is similar to that of light traveling in space, long
after the star which originated it has been destroyed. Or, again, it is
like the vibrations of heat remaining in a room after the lamp or stove
causing it has been removed, or the fire in the grate having died out.
Or like the sound waves of the drum-beat persisting after the beat
itself has ceased. It is all a matter of the persistence of vibrations.

Thought forms differ greatly one from the other in the matter of shape
and general appearance. The most common and simple form is that of an
undulating