Especially when an economic crisis occurs, such as the last big crisis in 2008, contemporaries tend to question certainties of belief systems including academic systems of knowledge. Paradigms evolve to become a subject of inquiry. One of those new topics is the need to increasingly acknowledge history of economic thought (HET) as an important, although neglected, domain of economic inquiry. During the last few decades, HET has mostly been abolished or has disappeared in many contemporary teaching curricula in economics. An unforecasted crisis teaches us the lesson that our academic understanding may be incomplete. However, can we learn anything by reading the HET literature? The answer is that HET makes current debate less sterile because it embeds the matter into a flux of changing paradigms. Many brilliant argumentations exist hinting to the fact that HET has to be interpreted as a permanent over-writing process of academic failures by which we can learn about directions in new knowledge. The paper distinguishes between history of intellectual ideas and economic history. Both items have to be discussed separately when analyzing their methodological appropriateness and benefits. Economic theory as a body of common knowledge is never stationary nor stable as a set of monolithic systems of academic belief but is always embedded in changes in intellectual thought and related processes of struggle. A science lacking a necessary understanding of the roots of the subject is hard to accept. A graduate in economics who has never read a single line of one of the heroes of economics is a tragic caricature of a professional person. But, there are also systematic reasons such as, new knowledge in economics is made up of, above all, old particles of knowledge combined in new ways.