The ungrounded belief that money and markets are the solution to all social problems.  True believers attempt to ground their belief in an analogy between the competition that is one of the processes in the evoludion of living species and competition in financial and labor markets.  It might be reasonable if there were not so many flaws in the analogy, but the deeper problem is that markets are constructed and can be distorted in many ways, and the biological imparitives of existence and survival are ultimately within a single shared environment with only a few specific environmental externalities.  Other than the incoming solar energy, the biosphere is a closed system, the economy is not.