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We observe that the big six of the basic emotions have evolved for our own protection.
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We observe that the big six of the basic emotions have evolved for our own protection. The studies in New Guinea that show that emotion recognition of facial features is consistent across cultures is amazing. The further studies that show we can back feed our emotional system to some extent simply by mimicking the common associated facial features is also amazing. Now we know why grandma would say " put on a happy face and you will feel better" when you were sent off to school.
As Justine and Fallon pointed out research is already making great strides in chemically effecting the sadness emotion. There is still a long way to go though in understanding the subtleties of the systems involved. We all know people whose meds are either too much or too little or just plain wrong. I know of one case where it has taken decades to get just the right combination for this person to have a somewhat normal life.
But what about the other emotions what if you could target anger. What if you could make people angry all the time? But wait they can already do that. It is called right wing talk radio. As a group people that listen to talk radio are the angriest bunch. Try discussing it with them and they get angrier still. As the recent election has shown, it doesn't take drugs to manipulate peoples emotions. Demagoguery is a time honored method of effecting emotions of the masses. We can also observe how unethical it is.