Ba
bꜣWhat it is
The mobile, individual part: personality and the capacity to act, shown as a human-headed bird.
What it needs after death
To leave the tomb by day and return to the body at night. If it cannot find its way back, the person is finished.
What “soul” loses
That it MOVES, which the ka does not. Most of what a coffin is designed to do, the false door, the shaft, the painted eyes, is architecture for the ba's daily commute.
The other parts
Ka
kꜣThe vital essence, created at birth on Khnum's potter's wheel alongside the body, and the thing whos...
Akh
ꜣḫWhat a person becomes if everything works: ba and ka successfully reunited after death, transfigured...
Ren
rnThe name, treated as a real component of a person rather than a label attached to one.
Sheut
šwtThe shadow, understood as a real part of a person and as something with its own presence and protect...
Ib
jbThe heart: the seat of thought, memory, will and character, and the organ that testifies at the judg...