Further Contra Uncertainty
• John Vandivier
This article further criticizes the notion of Knightian uncertainty which is often used to attack equilibrium theory. Section II highlights some past work.
I recently watched and old debate between Caplan and Boettke. The debate focuses on the validity of Austrian economics, but my focus is on Bryan's criticism of uncertainty.
See 5:41 of this clip where Bryan begins a rebuttal. He claims that Neoclassical Search Theory, properly implemented, can overcome objections about uncertainty.
He likens uncertainty to serendipity or pleasant surprise. He proceeds to claim that this can be modeled as an ordinary search theory model with some additional baseline return.
His point is well taken, but let me present the objection Boettke should have raised: Uncertainty cannot be modeled with a baseline benefit. It might consist of a baseline cost. Moreover, the baseline benefit is unknown. As a result, the proper search theory representation of uncertainty would be the following:
F(t) is the outcome expected under uncertainty. f(t) is the underlying search-theoretic functional form, trivially supposed as a function of time. k is the uncertainty modifier. As you can see, because k is uncertain the entire function collapses into uncertainty and the search theoretic result is undecidable. This is the inevitable result from uncertainty and it is the conclusion of George Shackle's radical uncertainty, although it is also called Knightian risk, sheer ignorance, or simply uncertainty. Applied to equilibrium theory, it would entail that we have no reason to believe the economy is generally equilibrating in the long run, or any run.
Now let me defend search theory against the above criticism:

- If such were the case then the economy would not predictably improve, but it does.
- If such were the case then equilibrium theory and neoclassical price theory would be empirically impotent, but they aren't.
- If such were the case then individuals would not be able to rationally connect any particular action to an expected value, but they do.
- Corollary to 3, human action would not be observed, but it is.
- Horizontal linear distribution
- Symmetric angled linear distribution
- Either of these. I'm not convinced at this time that logic causes one to be preferred prior to the other.
- Asymmetric linear distribution
- Symmetric non-linear distribution
- Asymmetric non-linear distribution
- Categorical Certainty: Contra Radical Uncertainty
- Forecasting and Austrian Economics
- Short Essay Regarding: “The Use of Knowledge in Political Economy: Paretian Insight into a Hayekian Challenge”
- Rational Estimation and Price Under Uncertainty
- Statistical Reasoning with Uncertainty
- A Priori Probability: Larger Values