Our society needs diversity to thrive. If we have a society made up of only people that know 'useful' things (or what is considered useful today, as this change

Our society needs diversity to thrive. If we have a society made up of only people that know 'useful' things (or what is considered useful today, as this changes through time), it becomes vulnerable, in the same way that a population with a narrow gene pool is vulnerable. So, it's important that we have people who understand the causes of the second world war (history) or the difference between signifier and signified (semiotics) in the same way that it's important we have people who understand about the viscosity of fluids; our society is all the poorer without them.