Those capable of practicing the martial arts, and not everyone can, has a particular mutated gene known as HACNS1 (also known as CENTG2), that improves ones coordination and dexterity. The gene is responsible for the evolution of the opposable thumb and modifications in the foot and ankle that allow humans to walk upright. When this gene mutates in certain humans, it leaves them with astounding physical abilities. This mutated gene can give one the power to leap up to 9 feet in the air, catch a descending sword blow in the palms of the hands, or tunnel downward at amazing speed to hide from a potential threat.
When mutated HACNS1 is found in humans, particularly males, and is combined with the serotonin 5HT, this can lead to elevated aggression, and elevated aggression is what's needed for the martial arts assassin. So, based on these facts, it makes absolutely no sense that the martial arts would be a self defense discipline.
Consider the popular sport MMA, a sport rife with outright male hostility and aggressive behavior. these individuals who participate in this sport strictly use the martial arts during a match. It's safe to assume that these men fit the parameters described above.
The only thing stopping MMA participants from killing each other, once one fighter has been subdued, is a referee who carries a small hand- held injector that he applies to an overly aggressive fighter trying to kill his unconscious opponent. The drug soothes the fighter and delivers to his brain a sense of well being and elation, this leads to the victors typical joyous display after he realizes the fight is over and he is the conquering combatant. Arms in the air, the winner stares glassy-eyed to an adoring crowd, unaware he's been manipulated by a mood-altering agent.
note- In the youtube video, notice the referee slyly touch the winning fighter's arm and the celebration that ensues afterward.
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