"Unionization, as opposed to communism, presupposes the relation of employment; it is based upon the wage system and it recognizes fully and unreservedly the institution of private property and the right to investment profit"

John L. Lewis' quote is a contrast between unionization and communism. He is emphasizing that unionization is based upon the wage system and respects the institution of personal property and the right to investment earnings. This is in contrast to communism, which does not acknowledge the wage system or private property. Unionization is a form of collective bargaining between employers and staff members, where staff members have the ability to negotiate much better salaries and working conditions. It is a way for workers to have a say in their working environment and to ensure that their rights are respected. Lewis' quote is a pointer that unionization is a viable alternative to communism, which it is a way for employees to have a voice in their workplace.