Ludwig von Mises discussed actors in a section of his book The Anti-Capitalist Mentality (Chapter 1 Section 9: The Communism of Broadway and Hollywood). I never thought that Mises fully answered the question in that section. He blamed it on the fear actors have that they may lose the adoration of the public and fall to the wayside. But, I think there is probably more. One important fact is that actors tend to use the imagination part of their brain for their work, rather than the logical part.
According to Professor Sophie Scott, from UCL's Institute of Cognitive Neuroscience, professional actors use a part of the brain that is called the infra parietal sulkus, when they attempt to create a voice for a character and recite lines. Most fascinating only the pros use it to create a voice not the rest of us.
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So in the clip below, when Affleck says he is in favor of TSA dick grabbing, is he thinking this out logically about the totalitarian implications of TSA dick grabbing or is he using the imagination part of the brain, that most of us don't use, in a near imaginary world where he is in someway Jack Ryan fighting imaginary terrorists?