Some choice quotes:
Austrians were in the forefront of the Marginalist revolution; an advance which realized that choices are made (and hence valuations formed) "at the margin." This alone was enough to correct errors which had long confounded both classicists and Marxists.
It is the entrepreneur's particular skill—as well as his essential service to society—that he has an enhanced ability to put temporarily underpriced combinations of resources to a more nearly optimal use than can other men.
Mises himself single-handedly destroyed any attempts to construct a socialist rationale in the famous "calculation debate," showing that, without private property and an unhindered price mechanism, production can never be properly coordinated to allocate scarce resources to their best and most urgent uses.
Menger and Boehm-Bawerk, et al.,derived the most satisfying theory of the origins of interest—the so-called natural rate being, essentially, a measure of mortal man’s inherent impatience with any delay in the gratification of his wants and needs.
Hazlitt, developing this theme, wrote that the "One Lesson" of economics is that there is no such thing as a free lunch and that we must always look beyond the immediate results of an action to see its hidden and indirect influences before we pronounce it a success or a failure.
[Austrian economics] does not confuse money with wealth; it knows that production delivers prosperity, not consumption.