The notion that the physical body of man is as it were the exteriorization of an invisible subtle embodiment of the life of the mind is a very ancient belief. It is however, the prevailing habit of skeptical rationalism of the present day to dismiss summarily all such beliefs of antiquity as the baseless dreams of a prescientific age, and to dump them all indiscriminately into the midden of exploded superstitions. Not only do the acute intellects who upheld it in the past, dispose one to a favorable consideration of their plea; but I am persuaded that, the more deeply modern research penetrates into the more recondite regions of biology, psycho-physiology and psychology, the more readily will reason be inclined to welcome the notion as a fertile working hypothesis to co-ordinate a considerable number of the mental, vital and physical phenomena of human personality which otherwise remain on our hands as a confused and inexplicable conglomerate. Contents: The Spirit-Body; The Radiant Body; The Resurrection-Body; Epilogue.