The primitive man lives almost exclusively in the physical world, spending only a few years in the astral at the end of each of his physical lives.

As he develops, the astral life becomes longer, and as intellect: unfolds in him, and he becomes able to think, he begins to spend a little time in the mental world as well.

The ordinary man of civilized races remains longer in the mental world than in the physical and astral; indeed, the more a man evolves the longer becomes his mental, life and the shorter his life in the astral world.
The astral life is the result of all feelings which have in them the element of self.

If they have been directly selfish, they bring him into conditions of great unpleasantness in the astral world; if, though tinged with thoughts of self, they have been good and kindly, they bring him a comparatively pleasant though still limited astral life.

Such of his thoughts and feelings as have been entirely unselfish produce their results in his life in the mental world; therefore that life in the mental, world cannot be other than blissful.