William Walker Atkinson 
Reincarnation in Ancient and Modern Cultures 

There are many forms of belief—many degrees of doctrine—regarding Reincarnation, as we shall see as we proceed, but there is a fundamental and basic principle underlying all of the various shades of opinion, and divisions of the schools. This fundamental belief may be expressed as the doctrine that there is in man an immaterial Something (called the soul, spirit, inner self, or many other names) which does not perish at the death or disintegration of the body, but which persists as an entity, and after a shorter or longer interval of rest reincarnates, or is re-born, into a new body—that of an unborn infant—from whence it proceeds to live a new life in the body, more or less unconscious of its past existences, but containing within itself the "essence" or results of its past lives, which experiences go to make up its new "character, " or "personality."