Which one of the following canons of taxation was not advocated by Adam Smith?

Adam Smith, in his seminal 1776 work 'The Wealth of Nations', formulated four fundamental principles or 'canons' of taxation to guide effective tax administration. These include the Canon of Equality (or Equity), which suggests taxes should be based on the taxpayer's ability to pay; the Canon of Certainty, requiring that the tax amount and time of payment be clear; the Canon of Convenience, stating taxes should be collected when most convenient for the payer; and the Canon of Economy (or Efficiency), which dictates that the cost of collection should be minimized [1]. While modern economists like Charles Bastable introduced additional principles such as the Canon of Fiscal Adequacy (ensuring the tax system generates sufficient revenue for state needs), this was not part of Smith's original four canons [1]. Therefore, fiscal adequacy is the correct answer as it was not advocated by Smith.

Sources

1. [1] https://mathabhangacollege.ac.in/wp-content/uploads/2024/02/CANONS-OF-TAXATION_compressed.pdf