Comment on Jackson's analysis of electric charge quantization due to interaction with Dirac's magnetic monopole

Abstract. In J.D. Jackson's Classical Electrodynamics textbook, the analysis of Dirac's charge quantization condition in the presence of a magnetic monopole has a mathematical omission and an all-too-brief physical argument that might mislead some students. This paper presents a detailed derivation of Jackson's main result, explains the signicance of the missing term, and highlights the close connection between Jackson's ndings and Dirac's original argument.