Scarce resources are required to produce each of them. For example, the buildings, labor, and other resources used to produce schooling could be used instead to produce more food, recreation, entertainment, or other goods. The cost of the schooling is the value of those goods that must now be given p because the resources required for their production were instead used to produce schooling. Governments may be able to shift costs, but they cannot avoid them. Voluntary exchange promotes economic progress.
Mutual gain is the foundation of trade.
Parties agree to an exchange because they anticipate that it will improve their well-being. First, trade channels goods and services to those who value them most. A highly technical book on electronics that is of no value to an art collector may be worth hundreds of dollars to an engineer. Similarly, a painting that is unappreciated by an engineer may be an object of great value to an art collector. Second, exchange permits trading partners to gain from specializing in the production of those things they do best.