As Renaissance society increasingly depended on trade and commerce, new business practices were established. For example, merchants developed the concept of credit to facilitate the management and transfer of large sums of money, particularly in dealing with distant countries. Renaissance accountants invented double-entry bookkeeping, in which every transaction is entered in both a credit and a debit account, to assure balanced books and make possible more sophisticated analysis of the true costs and profits of a business.

The Importance of Math and Law

However, at the beginning of the Renaissance, many people were poor at math. According to John Hale, even literate men "were seldom able to do more than add and subtract, double and halve." Most people could not perform computations with fractions, nor did they learn the multiplication table. Moreover, Hale reports, "Addition and...