So the issue is - is it possible to produce a valid measurement? In scientific method, part of an experiment involves a control. There&#x27;s no way to produce one in economics - the systems are too complicated. You can&#x27;t know whether measurements you take are the result of your change directly, or caused by network effects of the change as part of other things going on, or just weather from unrelated things happening in the economic system.<p>Austrian instincts are partly about building a defense against corruption and tyranny. If you let politicians spend money or introduce mechanisms that are difficult to measure, or which can be easily hand-waved away (&quot;we did what we thought was right based on the information at the time&quot;), then they are incentivised to spend. Instead, they form a line in the sand and say that you&#x27;re not allowed to do anything which can&#x27;t be clearly justified from a set of first principles. The back-story is not so much a faith in the inherent goodness of markets as in the inherent evilness of governments.