Libertarian in the sense of social libertarianism, not economic. (Basically anarchist.) No classes or nation states, free association between people instead of strict governments. As opposed to state socialism with its nationalization of industry, state ownership of property, state ownership of industry and means of production and its central economic planning. (What most people unfortunately think of when they think of socialism. I disagree with it too.)
Land, means of production, firms, etc. not owned privately by a firm or publicly by the state but collectively. Firms organized by worker-owners, not by one boss, i.e., worker's self-management and decentralized planning by the worker-owners of the firms. This should explain it better than I could.
[link]Basically how people lived for most of human history, the mindset emphasizing cooperation over competition.
I think I sent you this article before, but it explains how a free-market economy could work in all of this.
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