A remarkable, unquestioned assumption in studies measuring the association between national average Intellectual Quotients (IQ) and Gross Domestic Products (GDP) per capita is that a supposedly immutable genetic factor (IQ) may be correlated with a markedly fluctuant one (the wealth of nations). Using historical GDP per capita data produced by the Maddison project, we find that, over history, the (Pearson productmoment) correlation coefficient (r) between average IQ and GDP per capita is highly variable and ranges from strong negative values to strong positive values. The correlation between national IQ and GDP per capita is thus a snapshot of the world order at some point in time, and historical data allow us to identify several other eras. Moreover, global GDP at any point in time is never difficult to predict in the first place. We show that arbitrary ad-hoc scores based on a country’s continental location present a more significant correlation with contemporary GDP per capita. We conclude this paper by a call to clarify the purpose of IQ studies in Macroeconomics and for the consideration of GDP as a time-series in this line of research.