How Many Souls a Person Has
A single indivisible soul, now the default assumption in most Western thinking, is actually the minority position historically, owing mainly to later Christian and Cartesian philosophy. A popular modern attempt to map all these different ancient systems onto one unified 'seven bodies' scheme is itself a nineteenth-century Theosophical harmonisation, not a shared ancient finding.
Egyptian ka, ba and akh; Chinese hun and po, separating at death in Han-era texts; Norse hamr, hugr and fylgja
The idea, found independently in Egyptian, Chinese, Greek and Norse sources, that a person possesses several distinct soul-components rather than one unified soul.