Television watching is almost always a passive undertaking. It is not something that requires focus, like using a computer or playing a video game. It does not require that you do anything. You will not be tested afterward to see if you have learned the material.
An art instructor, a very long time ago, was complaining about budget cuts to his program, and said that art relaxes the mind. Television can also relax the mind, albeit it is often in a mostly idiotic way.
Everyone needs to rest their minds. Many people go to work every day, and I am not one of them, come home and need to obtain a little bit of escapism. If you are mentally ill, sometimes escapism and resting the mind are exactly the things you need to get off the track of worrying, being upset, and possibly having symptoms.
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