* The face is a transponder – the outward reaching organs of the head take in readings from ambient local and the feedback process is effectively instant and wholly involuntary.

* Accomplished actors and effective sales professionals may be capable, through long practice or genetic circumstance, of controlling the minutiae of their expression to some degree. It is said that even the reflexive action of the pupils in widening on rapport or engagement can be brought into the voluntary.

* There is a branch of the social sciences which deals with determination of veracity through the examination of microexpressions.

* There’s an episode in Lone Wolf and Cub when Itto is hunted by a ninja who has undergone specialized conditioning so that he is incapable of demonstrating any expression on his face. This incapacity to demonstrate feeling removes him from the realm of compassion and he kills implacably. His method is to kill anyone who comes into any kind of contact with Itto – any aid, any interaction, even a glance of friendliness in passing on the road results in murder. In the end, Ogami Itto wins victory through austerity measures, retreating to the winter mountains, hunting for his food, huddling with Daigoro between night wind and fire. With no means to employ his method the assassin is denied expression of his craft just as he is denied his feelings. Fixed, incapable of breaking away, the stone faced ninja starves in the snow.

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