As the Cambridge economist Joan Robinson (1903-1983) put the matter in 1962 in Economic Philosophy:
“All along [economics] has been striving to escape from sentiment and to win for itself the status of a science … [but] … lacking the experimental method, economists are not strictly enough compelled to reduce metaphysical concepts to falsifiable terms and cannot compel each other to agree as to what has been falsified. So economics limps along with one foot in untested hypotheses and the other in untestable slogans”.
I reckon that says it in a nutshell.
And yet a great many people including many economists continue to suppose that economics can be a bona fide science. Worse: a great many people – including many scientists, who really should know better – further suppose that science will in time tell us all there is to know and is worth knowing if only we do enough research; that science can indeed lead us to omniscience; and that the “high” technologies that science gives rise to will eventually make us omnipotent. This is a huge and hugely damaging mistake, as discussed elsewhere on this website. But many economists do see economics as a science, and also see science as the royal road to truth, and so fall foul of a double whammy. They mistake the true nature both of economics and of science. The over-confidence of the neoliberals, manifest of late in the economic excesses of Liz Truss and Kwasi Kwarteng, shows the folly of this (see Further Thoughts under Governance).
Incidentally, in the year that Joan Robinson published Economic Philosophy (1962) the American philosopher Thomas Kuhn (1922-1996) published The Structure of Scientific Revolutions, and launched the idea of the “paradigm shift” and so helped to undermine the notion that science can lead to omniscience. All in all the 1960s was a great decade for the phil of sci (to be discussed). But big ideas however important can be slow to catch on, especially when they are inconvenient to people in positions of influence. So despite the conceptual advances the old misconceptions re the nature and the power of science and of economics, which date in effect from the 17th and 18th centuries, live on, and are taught, and acted upon.