What you see here is one of the characteristics of libertarians like Greenspan. The ability to hold mutually contradictory ideas simultaneously.

I've mentioned this before, but it's worth repeating: psychologist Robert Altemeyer's free online book:
http://theAuthoritarians.com

He finds a correlation between the "authoritarian" personality and conservative political viewpoints. Libertarians are not in the same class, but they do share these key psychological characteristics.

The other one is their immunity to facts that disprove their beliefs.

Policies not Politics
---- Daily Landscape