Well, TEK, studying history is always a good idea. So is studying biological science, neurology, psychology, etc.

Up until the time of the Industrial Revolution, mankind worked 20 hours per week. Also, alll mammals have a 20 hour work week, i.e. the time they spend looking for food and organizing shelter, etc. So, no, I did not pick 20 hours for 'rhetorical purposes.' I picked that number because it is the number mankind evolved to work without undue stress.

Yes, I do think all labour is equal. I do not think some people are superior to to others because they are genetically able to calcuate maths or they are born in a time when brawn is more important than brain or visa versa. All human life has worth. And I see no reason why some people should starve while others, as a result of their warped sense of self-importance, should earn six times more than they need.