Amongst the qualifications necessary for the production of treatises on popular psychology a flair for seductive, if somewhat awe-inspiring, titles seems to rank very highly indeed. But in justice to Dr. Hinkle, it must be added that at the very outset she endeavours to allay any trepidation which scrutiny of her title page may arouse. She is at pains to assure us that no attempt has been made to hold words to one particular meaning; and when, on the following page, she refers to psychic disturbances for which she can give 'no other name than soul sickness', the comforting thought arises that if at times her exposition induces perplexity, it is a state of mind which is shared on occasion by the authoress herself.