Debt’s a popular subject right now. But writers have been thinking about it for years.

The relationship between literature and debt, though, is not just a matter of impoverished novelists scribbling to keep themselves out of the clink. The business of lending has also generated literary riches. John Milton was the son of a scrivener, who (like most members of his profession) regularly made loans for interest. This income supported his unemployed son through his early periods of study at Hammersmith and Horton, and enabled him to become the most learned poet of any age. Debt also shaped Milton’s personal life: his first unhappy marriage was to Mary Powell, whose father owed the elder Milton £300, which he never repaid.

Until quite recently debt was not regarded as a purely financial matter. Money was generally lent to people whom you knew, and financial ties between households could be sealed by marriages. You lent to people whose social status encouraged belief (hence “credit”) that they were reliable. This complex idea of credit – part financial, part moral, part social – goes back a long way. In Chaucer’s Shipman’s Tale the merchant states a general truth that we can only borrow “while we have a name” (ie a good reputation). And because lending money was linked with social and erotic relationships, a financial debt could be repaid in any number of ways. So in the Shipman’s Tale the merchant lends money to his “cousin”, a friar, which the friar lends in turn to the merchant’s wife. She sleeps with the friar and then with her husband to repay the debts. For most of our ancestors, debt was not simply what we think of as debt. A metaphorical economy of status, friendship, sexual favours and trust existed in parallel to the monetary economy of financial exchange, profit and loss.

These parallel economies were vital to English writing. It meant that stories about debt could touch on almost any aspect of human relationships, from friendship to commerce. What would happen if someone of good credit (in the moral sense) borrowed money from someone who had lots of money but not much social standing? What sort of bonds and conflicts would result?