The "greater good" argument is a slippery slope and can be used to justify anything that someone thinks might benefit society. To me, a true public work is something that is in the interest of a society, BUT is in no one's particular interest. Examples would include building a dam to create a reservoir to prevent flooding or creating a road system are good examples. Getting an education is something that is in an individual's interest. It will get them a better job, earning more money, and getting better benefits than if they had not gotten that education. Since getting an education is in the individual's interest, they should pay for it. While having a better educated population is in the interest of a society, that goal can be achieved through individual's pursuing their own self- interests and paying for it themselves, rather than burdening other tax payers with the bill.