Capital

The word capital derives from the Latin caput, meaning head, through the adjective capitalis, meaning "of the head" or "chief."1 In Medieval Latin, capitale came to mean the principal sum of money, as distinct from the interest it earned, the "head" of a financial arrangement from which smaller amounts flowed.

English borrowed the word in the thirteenth century. By the early seventeenth century, capital was used to describe the stock of goods or money available for producing wealth. Adam Smith used the word throughout The Wealth of Nations in 1776 to describe the accumulated resources that fund productive activity.2

The metaphor embedded in the word is architectural. The head (caput) sits at the top of the body. In Roman architecture, a capital was the topmost element of a column, the part that bore the weight of what rested above it. The financial meaning followed the same logic. Capital was the foundation that supported everything built on top of it.

Karl Marx gave the word its fullest theoretical treatment in Das Kapital, published in 1867, arguing that capital was not merely money or goods but a social relation, the means through which one class extracted value from the labor of another.3

In the twentieth century, the word proliferated into compounds. Human capital treated people's skills as an economic asset. Social capital described the value of relationships. Cultural capital, coined by Pierre Bourdieu, named the knowledge and habits that confer social advantage.4 Each new compound extended the metaphor, treating something previously understood as human into something that could be measured, accumulated, and deployed.

The Latin word for head now governs the vocabulary of economics, finance, and social theory in virtually every language. The city where a government sits is a capital. The letter that begins a proper noun is a capital. The crime punishable by death is a capital offense. In every case, the word points to the same image. What sits at the top determines what happens below.