I. The Mind, Body, and Spirit are what make the parts of a man.
a. The Mind
1.

The mind records data using what are called mental image pictures. Such pictures are actually three-dimensional, containing color, sound and smell, as well as other perceptions. They also include the conclusions or speculations of the individual. Mental image pictures are continuously made by the mind, moment by moment.

Analytical Mind and Reactive Mind
The mind has two distinct parts. One of these — the part which one consciously uses and is aware of — is the analytical mind. This is the portion of the mind which thinks, observes data, remembers it and resolves problems. It has standard memory banks which contain mental image pictures, and uses the data from these banks to make decisions that promote survival.
In moments of intense pain and unconsciousness, the analytical mind is suspended and the reactive mind takes over. It records everything that happens during unconsciousness in its own banks, unavailable to the individual's conscious recall and not under his control. It has the power to react obsessively upon him at a later time, forcing irrational "solutions" on the individual.

The reactive mind can cause unknowing and unwanted fears, emotions, pains and psychosomatic illnesses that one would be much better off without. It holds a person back, getting in the way of his survival and success in life.
With Dianetics auditing, the contents of the reactive mind can be erased, freeing the person from its adverse influence. The previously hidden memories are now stored in the analytical mind, under the control of the individual.
A person who no longer has his own reactive mind is called a Clear. What he is left with is all that is really him, and with his mind's potential now fully available.

II. The Spirit
a. Thetan
1. The thetan is the source of all creation and life itself. It becomes fully apparent for the first time in man’s experience that the spirit is immortal and possessed of capabilities well in excess of those hitherto predicted. The exteriorization of the thetan from his body accomplishes the realization of goals envisioned — but questionably, if ever, obtained — in spiritualism, mysticism and such fields.
Recognition of the thetan makes possible gains in ability and awareness — improvements which are not attainable in any practice holding man to be only a body and thus entirely subject to physical universe limitations. Psychology, for instance, had worked itself into a dead end. Having no concept of the existence of an animating factor to life, it had degenerated into a practice devoted solely to the creation of an effect on living forms.
In Scientology, however, the thetan himself is directly addressed. Such an approach to improvement accomplishes increased spiritual freedom, intelligence and ability for the individual, and clarifies any part of life.
III. The Body
1. Carbon-Oxygen Machine
a. The Thetan Being The Engineer of this Machine, it is one of the less important parts of the body. For when it dies your spirit and mind live on.