SUMMARY. 153 



are nerve-muscular signs. A posture is the position 

 of a part of the body or a member, and is due in 

 its mechanism to the balance of its muscles. We 

 may, then, speak of the postures of any members 

 of the body, head, face, eyes, etc. It is in free or 

 disengaged members, or parts, that we see the best 

 examples of direct expression. A hand engaged in 

 labour is less expressive of mental conditions than 

 an unoccupied hand. Postures may be determined 

 by organic conditions rather than by the state of the 

 nerve-centres ; thus, the body is supported, when 

 there is urgent difficulty of breathing. In the 

 Dying Gladiator the body is supported by the arm 

 to assist the breathing. Gravity often determines 

 the position of the head and limbs, when there is no 

 strong nerve-current proceeding to its muscles. 



The position of a member may be due to reflex 

 action. Observation shows that a special posture 

 follows uniformly upon the stimulation of a par- 

 ticular sensory surface ; here the posture is not the 

 spontaneous outcome of what originates in the 

 subject, and the posture is less likely to indicate the 

 volition or the brain condition. Free and disengaged 

 parts are alone expressive of brain conditions. 



Postures may be due to organic disease, or to 

 changes in the joints ; in such cases they are not 

 direct indices of the brain. 



The effects of gravity are worthy of study ; they 

 are better understood in plant-life than in man. 



Postures may be classified in the same manner 

 as movements. We see examples of postures alike 

 in man, animals, and in plants ; in each case such 

 .signs are expressive. 



