There is only one condition in which we can imagine managers not needing subordinates, and masters not needing slaves. This condition would be that each (inanimate) instrument could do its own work.
Some people's eyes are large, others small, and some are medium-sized; the medium ones are best. And some eyes stick out, some are deep-set, and some are moderate, and deep-set eyes have the sharpest vision in all animals; the middle... ...
