( recorded here ) This is such a great question. And I can answer it from several or all points of view.
- First: any argument to principle is not argument to causality and can be generally interpreted as an attempt at deceit by the use of half truths in order to cause the individual to rely on intuition and therefore be the victim of suggestion.
- Second: the full sentence would be that man acts in his rational self interest at all times given his available information and his available means of understanding.
- Third: mises epistemology is a derivation of the kantian fallacy. Because while we can use free association to construct hypotheses, in the form of deduction, induction, and abduction (guessing), we cannot claim these to be truth propositions like we can in geometry, ( nor can we in geometry at scale either) because the information in reality is more causally dense than the ideal world of perfect imaginary mathematical categories. So for truth propositions we must ensure to perform due diligence that our discovery of a free association remains a truth candidate.
This is what the scientific method accomplished: due diligence against falsehood. That is all. And our success arises from eliminating many errors so that our free associations are increasingly superior.
What does this mean? It means that economic observations remain empirical – beyond direct perception. But that we must be able to explain any empirical observation as a sequence of subjectively testable voluntary operations in order for it to be a truth candidate. So Mises had it backward. All sciences require empirical observation to capture imperceptible phenomenon, but all truth claims must be warranted against error bias wishful thinking, suggestion and error, by acts of due diligence. The test of existential possibility and objective morality is performed praxeologically: by subjectively testing the sequence of operations necessary to produce the empirically observed phenomenon. I could go on at length here but this should be enough. IN CLOSING: It is obvious to me that just as anglos used martial empiricism and contractualism in their enlightenment. And just as Germans used hierarchical duty and rationalism as a restatement of Germanic Christianity. The Jews used the authoritarianism of Jewish law as a reformation of their religion. We can see mises like Freud, Marx, and Boaz as attempting to create an authoritarian pseudoscience using half truth and suggestion because Jewish law and religion is constructed by this method. My rather uncomfortable observation is that this technique like Jewish ghetto financing, is a pattern under which suggestion can be use to use temporal language to create seductive moral hazards from which they and profit. That mises had like Rothbard adopted this strategy metaphysically and involuntarily is obvious. Both men, like Marx, went to their graves knowing they were wrong but not knowing yet what assumptions in their cultural heritage caused them to err.