He linked the notion of a spontaneous order that forms when agents follow (often simple) rules with the idea of complex systems in the 1950s. This wa… - Bruce Caldwell

Critics argue that Hayek mixed a number of ethical and political philosophies in constructing his system, positions that do not necessarily cohere one with another and all of which have been independently criticized. … There are evident tensions as well between his earlier advocacy of planning a framework of law and his later enthusiasm for the gradual evolution of judge-made common law. Finally, Hayek's opinion that judges operating under the common law tradition are bound to draw "conclusions that follow from the existing body of rules and the particular facts of the case" has struck more than one observer as naive. If one is judging his work against the standard of whether he provided a finished political philosophy, Hayek clearly did not succeed.

There are two elements of Hayek’s background that justify our considering him an Austrian economist: first, that he was raised and went to university in Vienna in the first three decades of the twentieth century, and second, that when he finally decided on economics as his field of study, he was trained within the Austrian tradition in economics.

In his discussions of spontaneous orders, sometimes Hayek was simply trying to make the point that they exist; that is, he was trying to counter the claim that any beneficent social order needed to be constructed. This view was widespread when he first was writing; the mania for planning was then ubiquitous, so it was a point worth making. In later writings, Hayek sometimes did say, let’s trust to evolved orders rather than constructed ones, but then allowed that sometimes we needed to make piece-meal changes, and he gave no criteria for deciding.