Central banks, in his view, are shadowy institutions that exist to enrich the powerful and debase the currency. He said earlier this year, "We need to stop allowing secretive banking cartels to endlessly enslave us through monetary policy trickery."
That's the sort of alarmism that causes many people philosophically compatible with Paul to roll their eyes. His fetish for the gold standard finds few allies even among economists who favor free markets and low inflation.
But his views on monetary matters don't evoke fierce disagreement from his fellow GOP candidates. What makes them recoil is his rejection of military intervention in places like Iraq and Afghanistan, which he blames for squandering money and provoking anti-American terrorism.
But again, Paul laces useful insights with irrational paranoia. In Libya, President Obama might get points for insisting that NATO take the lead role. Not from Paul, who denounces the multilateral approach as "a victory for one world government" -- one of his curious obsessions. He has previously accused both Obama and George W. Bush of favoring one world government.
Paul often makes such detours into the strange or indefensible. The newsletters he put out in the 1980s and 1990s showed a penchant for crude bigotry against blacks ("animals") and gays. Paul disavowed the offending passages, claiming he never saw or approved most of them -- an implausible excuse for a publication carrying his name.
But his appeal in this campaign lies elsewhere, in his longstanding opposition to inflation, excessive spending and endless war. On those issues, Paul has not moved toward the Republican mainstream since 2008; the Republican mainstream has moved toward him. As he hurries off to his next event, he leaves the crowd behind him, but he seems to be pulling the party in his wake.