Rule of Thumb

The Rule of Thumb was a customary law in the Seven Kingdoms that limited the size of the rod a husband could use to chastise his wife. Its boundaries came into focus at a court held by Rhaenys Targaryen: the husband in the case offered the rod itself as evidence that it met the accepted limit, but the queen ruled that lawful size did not make every use of it lawful.

Meaning and Context

The account presents the rule within a broader custom that allowed a husband to chastise an adulterous wife. That right was described as established throughout the Seven Kingdoms, except in Dorne. The Rule of Thumb regulated the implement: the husband said his rod was no thicker than his thumb, and produced it to support his claim that he had acted within the law.

Rhaenys's Judgment

Rhaenys consulted her maesters and septons before deciding the case. She held that an adulterous wife could be punished, but joined that principle to a separate limit on the number of blows: the Rule of Six. In her ruling, the first six blows were lawful, while the remaining ninety-four exceeded the permitted punishment and constituted an offense against gods and people. The case thus distinguished the rod's lawful size from the lawful extent of its use.

Legal Significance

The husband was taken to the foot of the Hill of Rhaenys, where the dead woman's brothers gave him ninety-four blows with rods of lawful size. The outcome applied both limits at once: the Rule of Thumb governed the rods, while the Rule of Six governed the number of blows. The account says that from that day forward both became part of the common law, establishing the Rule of Thumb not merely as a claim made in court but as a recognized legal constraint.