It is known that Murray Rothbard has always been a critic of the radical subjectivist school, often labeling it as a nihilistic school. He states on Lachmann:
Ludwig M. Lachmann, who had been a disciple of Hayek in England in the l930s and who had written a competent Austrian work entitled Capital and Its Structure in the 1950s, was suddenly converted by the methodology of the English economist George Shackle during the 1960s
Basically he states that Lachmann was a true Austrian throughout his first half of his career but later turn to a Shackelian. This passage has a footnote and it claims that Lachmann’s Austrian work is in Capital and It’s Structure and his departure of his Austrian insights is seen in his From Mises to Shackle. But Rothbard is mistaken that these works are not consistent with each other. I would look at Chapter 2 of his Capital and It’s Structure, which highly emphasizes subjective expectations and what this implies to capital theory. Lachmann didn’t have a change in thought as Rothbard claims.
Rothbard also states:
An amusing but instructive event occurred on the occasion of the conference of American Austrians at Windsor Castle in the summer of 1976. Under the good offices of Professor Stephen C. Littlechild of the University of Birmingham, a kind of summit conference was arranged so that some of the American Misesians could meet the English Subjectivist School, as the Shackleians call themselves. The eminent Subjectivists at the meeting included the doyen of that school, Shackle himself, as well as Terance W . Hutchison, Jack Wiseman, and Brian Loasby. At one point, the Subjectivists were lamenting that they could not offer a program of graduate economics courses as alternatives to the neoclassical paradigm, since all they had produced were a few critical essays but no substantial body of economic theory. I replied in some surprise that there was indeed a great deal of systematic Austrian literature available, including works by Mises, the early Hayek, and my own work, in addition to volumes of Böhm-Bawerk and Frank A. Fetter, among others. The blank looks of incomprehension on the faces of the distinguished Subjectivists were a revelation of the enormous extent of the inherent gulf between Shackleian Subjectivists and Misesians.
I’m not really sure what of this is true. I don’t know much on Hutchison’s work, but Shackle appealed to Keynesianism (thus his label as a post Keynesian by many), Littlechild has works on policy (see his book Fallacy of The Mixed Economy, and especially Wiseman too, which most of his work revolves around policy (see “The Political Economy”, “Guidelines for Public Enterprise”, “Uncertainty, Costs, and Collectivist Economic Planning”… I’ll stop there, but there are plenty more). Brain Loasby has articles on economic theory too (see “Management Economics and The Theory of the Firm” and “Hypothesis and Paradigm in the Theory of the Firm”). If anything, they were probably stunned at Rothbard choices of reads because they already have confronted the (orthodox) Austrian literature. It is worth noting on the policy recommendations of the radical subjectivists. Unlike the “true” Austrians (the people at Mises Institute for example) who at least agree of free market econ, the radical subjectivist group (or the English subjectivists as Rothbard labels them) do not really agree on such a thing, it is a school of thought more interested in human action, subjective expectations, and what implies from that (something which the Austrian school should be concerned about). Also, the above radical subjectivist literature should also be useful to see that Rothbard’s claim of radical subjectivists as nihilists is one of a straw man and misrepresentation.