Why should you be (or buy) a warrior? Wouldn’t the world be better off if there were no warriors, even could be no warriors? Yes, maybe we’d be better off if good property rights would just enforce themselves. But given that there are already other warriors, then it can make sense for you to be (or buy) a warrior, to defend yourself against other warriors. Yes there are some positive side effects, such as increased technical innovation in war-tech related areas. But mostly one wars to block opposing war.
Why should you be (or buy) an academic, such as a philosopher or economist? It seems to me that often the main reason to hire or be an academic is to defend against other academics.
Consider philosophy. Yes human thinking is often sloppy, with sloppy categories and circular arguments. But mostly this doesn’t cause that many problems. What does go wrong is that some people specialize in noticing such sloppiness, and then using it to persuade us of particular conclusions. When philosophers ridicule a particular sloppy argument, they shame the conclusion that argument had supported, which is then taken as supporting whatever is framed as the obvious alternative conclusion.
For example, imagine you thought that the conclusions of scientists were reliable because they followed a “scientific method.” This creates an opening for a philosopher to point out there there really is no coherent scientific method. Most scientists don’t actually follow most of the supposed scentific methods, and different sciences follow quite different methods. You might then be tempted to conclude that the conclusions of scientists are not reliable at all.
Yes that conclusion doesn’t directly follow from the mere fact that science reliability had been supported by sloppy arguments. But yet, all else equal, the fact that the best argument for something isn’t as good as you’d expected is an anti argument. If one side has stronger looking arguments than the other side, that seems to support the first side. Which is why all sides need to hire philosophers to find support, and to ridicule sloppy opposing arguments.
Similarly, often the main reason to hire or be an economist is to defend against other economists. It is bad for your side if the economic arguments supporting it seem sloppy, shallow and unsophisticated relative to the arguments from the other side. Each side needs to hire economists to offer supporting arguments, just to stay in place.
I’m not saying that philosophers’ or economists’ efforts never make us all better off; I’m just saying there is more of a counter-acting war effect than many realize. Much of the waste of academia is status seeking – some patrons funding academics in order to raise their status relative to others. And another big chuck is due to partisans recruiting academics to war on their side of common divides.