I've decided that a person is unfit for the office of the presidency if they cannot demonstrate a basic understanding of austrian economics. For the last century only this branch of social science has an explanation for the cycle of booms and busts experienced as a result of monetary manipulation. Conservatives are unanimous in their public pronouncements against Keynesianism but there are few if any that are willing to throw off the shackles of controlled economies and unleash the free market. This is either a function of economic inertia, wherein, the difficulty of returning to a free market becomes more difficult and exponentially more painful with each passing year; or, these people don't really believe in free markets in the first place and are simply pandering.
Having said that, I think all of the remaining candidates have the capacity to understand the basics of human action or praxeology (as the larger discipline of Austrian Economics is more properly referred to by its founding fathers) if not the will. I remember during one of the early debates, Michele Bachmann talking about taking some von Mises to the beach for reading material and Gingrich hinting at a gold commission to study the return to sound currency. This is a testament to not only how much Ron Paul has accomplished, but how much we've fallen. He has been the lone voice crying in the wilderness for the better part of three decades and certainly the only one espousing the forgotten geniuses of market dynamics. Fortunately, the principles are not difficult to understand, because they are rooted in basic logic. If a=b and b=c. Then a=c. That's as difficult as the math in economics should ever be. Superimposing random variables on aggregate measurements of individual action, then presuming to divine the future from empirical evidence supposes that men are a collective mind, conditioned to operate in concert according to the past, and devoid of free will to change their actions according as their desire for different outcomes determines them.
Stated otherwise, it is impossible to predict, in an interdependent system, the impact of decisions made by a single actor within the system. The Butterfly Effect or Domino Effect can project the effects of small initial decisions far into the future, perhaps even exponentially so.
That computer you decide not to buy, might be the difference between profitability and loss for a shopkeeper, which may hasten his decision to close the business, which would cause employees to lose jobs, which may cause them to lose their homes, which may cause the price of homes locally to fall, which could slow down housing starts, putting even more laborers out of work, increasing the demand on charities to provide basic services, ad infinitum. However, the decision to save the $1000 might buy an unemployed researcher another month of rent and ramen in his studio apartment, where he's been carefully developing a cure for the common cold. We literally have no idea and it is impossible to know just how consequential and far reaching our seemingly inconsequential decisions are.
For this reason it is imperative that we learn to respect natural systems, in all their complex efficiency, and resolve to avoid meddling. It's time we recognized that the powerful forces of the free market cannot be controlled but by theft and plunder; that the damages of malinvestment lead to social unrest and discontent. It's time we make logic our litmus test for office.