When Mises used the term the "logical structure of the human mind," he   
was referring to the logic of employing means to achieve ends through   
time and without knowing, in advance, all of the characteristics of the   
outcome that are relevant to achieving the ends. Every distinctly human   
actor possesses this logical structure and uses it, according to Mises.   
(This is in Chapter 2 of Human Action.)  
  
There is no need to learn or discuss psychology in order to explore,   
through a series of exercises using imaginary constructions, the   
implications of the assumption that such a logical structure exists. Nor   
are values necessarily involved, except in the irrelevant sense that a   
person who carries out such an exploration is a human being with ends of   
her own.  
  
Suppose that two people, A and B, have reason to believe that a   
distinctly human actor wants to achieve a particular end and suppose   
that A proposes that one of the available means will best satisfy the   
end. Then B can use the principles of logic and relevance to evaluate   
the proposal. No psychology is needed here. And no values other than   
those defined by the assumed ends of the actor and the desire to   
evaluate the proposal are relevant.  
  
So far, I have referred only to an abstract proposal about a single   
actor. Now consider a proposal that a tariff will, in net, benefit a   
nation under clearly specified conditions. So long as the concept of   
benefit to a nation is defined clearly, this argument can also be   
evaluated according to the criteria of logic and relevance.  
  
Mises claimed to be carrying out just this kind of evaluation (see his   
discussion of judgments of value in the last chapter of Human Action.�   
To label Mises an ideologue either because he fails to write a   
psychology of the human mind or because he explores the implications of   
the assumption that distinctly human actors possess a mind with the kind   
of logical structure described above is wrong. To properly apply this   
label, one would have to show some kind of systematic bias in his   
evaluations of proposed market interventions.  
  
This, in a nutshell, is why I think that John's claim about Mises being   
an ideologue amounts to bashing. He did not discuss the interventions   
and did not identify a bias. And he did not understand the role of the   
"logical structure of the human mind" idea in Mises's effort to provide   
an epistemological basis for economics.  
  
Pat Gunning