Besides, there exists a reason for physical incongruity which does not hold psychically. Nature sanctions the one while she discountenances the other. Instead of the forethought she once bestowed upon the body, it receives at her hands now but the scantiest attention. Its development has ceased to be an object with her. For some time past almost all her care has been devoted to the evolution of the soul. The consequence is that physically man is much less specialized than many other animals. In other words, he is bodily less advanced in the race for competitive extermination. He belongs to an antiquated, inefficient type of mammal. His organism is still of the jack-of-all-trades pattern, such as prevailed generally in the more youthful stages of organic life--one not specially suited to any particular pursuit. Were it not for his cerebral convolutions he could not compete for an instant in the struggle for existence, and even the monkey would reign in his stead. But brain is more effective than biceps, and a being who can kill his opponent farther off than he can see him evidently needs no great excellence of body to survive his foe. The field of competition has thus been transferred from matter to mind, but the fight has lost none of its keenness in consequence. With the same zeal with which advantageous anatomical variations were seized upon and perpetuated, psychical ones are now grasped and rendered hereditary. Now if opposites were to fancy and wed one another, such fortunate improvements would soon be lost. They would be scattered over the community at large even it they escaped entire neutralization. To prevent so disastrous a result nature implants a desire for resemblance, which desire man instinctively acts upon. Complete compatibility of temperament is of course a thing not to be expected nor indeed to be desired, since it would defeat its own end by allowing no room for variation. A fairly broad basis of agreement, however, exists even when least suspected. This common ground of content consists of those qualities held to be most essential by the individuals concerned, although not necessarily so appearing to other people. Sometimes, indeed, these qualities are still in the larvae state of desires. They are none the less potent upon the man's personality on that account, for the wish is always father to its own fulfilment.