It is probably no accident that the formation of classes and the relation between classes were first studied in the attempt to analyze the principles of conceptual reasoning. It should be clearn now that the same kind of relationship which in logic has been developed as the theory of classes and relations is immediately applicable to that physiological process of multiple grouping or classification which we have been examining. (6.48)
In other words, logic is the natural extension from how our brains do in fact work. One of course in turn can use logicl to further clarify and refine thinking. Now, if logic is in fact how we perceive the world and logic is how we think and categorize the world, then one should use logic to try to understand the world. This is Mises' argument for what is and should be the proper methodology of economics -- for which it seems Hayek is providing the mental foundation. All things within our perception, then, are properly understood using logic; if economic behavior is properly understood as emerging out of action, then one needs to use deductive logic.
If this is true, might Hayek have been more of a Misesian than most people realize? Or, perhaps, more than even he realized?