Yanis Varoufakis talks about the neoclassical economic tradition and its (futile and detrimental) attempt to quantify non-quantifiable phenomena. Such a debate has been raging on in the social sciences for quite some time, and continues today. Theodor Adorno and critical theory offers a important theoretical contribution to this debate (though such a rejection of the imperative to quantify everything goes back to Karl Marx and Max Weber), and I cannot recommend Adorno’s Introduction to Sociology enough (though Varoufakis has a ton of good lectures and debates on YouTube as well).
[It might be necessary to comment on Varoufakis’ sex appeal, perhaps best exemplified by pictures of him wearing leather and riding his motorcycle (to the left is an article of him in Germany’s tabloid magazine, Bild). It reminds me of C. Wright Mills, another great sociologist, who would ride his motorcycle – which he assembled himself – onto campus every day.]