The ancient Egyptians postulated seven souls.

Top soul, and the first to leave at the moment of death, is
Ren the Secret Name. This corresponds to the Director. He
directs the film of your life from conception to death. The Secret
Name is the title of your film. When you die, that's where Ren
came in.

Second Soul, and second one off the sinking ship, is Sekem.
Energy, Power, Light. The Director gives the orders, Sekem
presses the right buttons.

Number three is Khu, the Guardian Angel. He, she, or it is
the third man out...depicted as flying away across a full moon,
a bird with luminous wings and head of light. Sort of thing you
might see on a screen in an Indian restaurant in Panama. The
Khu is responsible for the subject and can be injured in his
defense--but not permanently, since the first three souls are
eternal. They go back to Heaven for another vessel. The four
remaining souls must take their chances with the subject in the
Land of the Dead.

Number four is Ba, the Heart, often treacherous. This is a
hawk's body with your face on it, shrunk down to the size of a
fist. Many a hero has been brought down, like Samson, by a
perfidious Ba.

Number five is Ka, the Double, most closely associated with
the subject. The Ka, which usually reaches adolescence at the
time of bodily death, is the only reliable guide through the
Land of the Dead to the Western Lands.

Number six is Khaibit, the Shadow, Memory, your whole
past conditioning from this and other lives.

Number seven is Sekhu, the Remains.

--Norman Mailer--

(as paraphrased in The Western Lands by William S. Burroughs)

see also Egyptian Mythology